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Linux 2.6 - man page for gpg (linux section 1)

GPG(1)					GNU Privacy Guard				   GPG(1)

NAME
       gpg - OpenPGP encryption and signing tool

SYNOPSIS
       gpg [--homedir dir] [--options file] [options] command [args]

DESCRIPTION
       gpg  is the OpenPGP part of the GNU Privacy Guard (GnuPG). It is a tool to provide digital
       encryption and signing services using the OpenPGP standard. gpg features complete key man-
       agement and all bells and whistles you can expect from a decent OpenPGP implementation.

       This  is  the  standalone  version of gpg.  For desktop use you should consider using gpg2
       ([On some platforms gpg2 is installed under the name gpg]).

RETURN VALUE
       The program returns 0 if everything was fine, 1 if at least a signature was bad, and other
       error codes for fatal errors.

WARNINGS
       Use a *good* password for your user account and a *good* passphrase to protect your secret
       key. This passphrase is the weakest part of the whole system. Programs  to  do  dictionary
       attacks	on  your  secret  keyring  are	very easy to write and so you should protect your
       "~/.gnupg/" directory very well.

       Keep in mind that, if this program is used over a network (telnet), it is *very*  easy  to
       spy out your passphrase!

       If you are going to verify detached signatures, make sure that the program knows about it;
       either give both filenames on the command line or use '-'' to specify STDIN.

INTEROPERABILITY
       GnuPG tries to be a very flexible implementation of the OpenPGP standard.  In  particular,
       GnuPG implements many of the optional parts of the standard, such as the SHA-512 hash, and
       the ZLIB and BZIP2 compression algorithms. It is  important  to	be  aware  that  not  all
       OpenPGP programs implement these optional algorithms and that by forcing their use via the
       --cipher-algo, --digest-algo, --cert-digest-algo, or --compress-algo options in GnuPG,  it
       is  possible  to  create a perfectly valid OpenPGP message, but one that cannot be read by
       the intended recipient.

       There are dozens of variations of OpenPGP programs available, and each supports a slightly
       different subset of these optional algorithms.  For example, until recently, no (unhacked)
       version of PGP supported the BLOWFISH cipher algorithm. A message  using  BLOWFISH  simply
       could  not  be read by a PGP user. By default, GnuPG uses the standard OpenPGP preferences
       system that will always do the right thing and create messages  that  are  usable  by  all
       recipients,  regardless of which OpenPGP program they use. Only override this safe default
       if you really know what you are doing.

       If you absolutely must override the safe default, or if the preferences on a given key are
       invalid	for  some  reason,  you  are  far  better off using the --pgp6, --pgp7, or --pgp8
       options. These options are safe as they do not force any particular algorithms  in  viola-
       tion of OpenPGP, but rather reduce the available algorithms to a "PGP-safe" list.

COMMANDS
       Commands  are  not distinguished from options except for the fact that only one command is
       allowed.

       gpg may be run with no commands, in which case it will perform a reasonable action depend-
       ing  on the type of file it is given as input (an encrypted message is decrypted, a signa-
       ture is verified, a file containing keys is listed).

       Please remember that option as well as command parsing stops as soon as	a  non-option  is
       encountered, you can explicitly stop parsing by using the special option --.

   Commands not specific to the function

       --version
	      Print the program version and licensing information.  Note that you cannot abbrevi-
	      ate this command.

       --help

       -h     Print a usage message summarizing the most useful command line options.  Note  that
	      you cannot abbreviate this command.

       --warranty
	      Print warranty information.

       --dump-options
	      Print  a list of all available options and commands.  Note that you cannot abbrevi-
	      ate this command.

   Commands to select the type of operation

       --sign

       -s     Make a signature. This command may be combined with --encrypt  (for  a  signed  and
	      encrypted message), --symmetric (for a signed and symmetrically encrypted message),
	      or --encrypt and --symmetric together (for a signed message that may  be	decrypted
	      via  a  secret  key  or a passphrase).  The key to be used for signing is chosen by
	      default or can be set with the --local-user and --default-key options.

       --clearsign
	      Make a clear text signature.  The content in a clear  text  signature  is  readable
	      without  any special software. OpenPGP software is only needed to verify the signa-
	      ture.  Clear text signatures may modify end-of-line whitespace for  platform  inde-
	      pendence	and are not intended to be reversible.	The key to be used for signing is
	      chosen by default or can be set with the --local-user and --default-key options.

       --detach-sign

       -b     Make a detached signature.

       --encrypt

       -e     Encrypt data. This option may be combined with --sign (for a signed  and	encrypted
	      message),  --symmetric  (for  a message that may be decrypted via a secret key or a
	      passphrase), or --sign and --symmetric together (for a signed message that  may  be
	      decrypted via a secret key or a passphrase).

       --symmetric

       -c     Encrypt  with  a	symmetric cipher using a passphrase. The default symmetric cipher
	      used is CAST5, but may be chosen with the --cipher-algo option. This option may  be
	      combined	with --sign (for a signed and symmetrically encrypted message), --encrypt
	      (for a message that may be decrypted via a secret key or a passphrase),  or  --sign
	      and --encrypt together (for a signed message that may be decrypted via a secret key
	      or a passphrase).

       --store
	      Store only (make a simple RFC1991 literal data packet).

       --decrypt

       -d     Decrypt the file given on the command line (or STDIN if no file is  specified)  and
	      write  it to STDOUT (or the file specified with --output). If the decrypted file is
	      signed, the signature is also verified. This command differs from the default oper-
	      ation,  as  it  never  writes  to the filename which is included in the file and it
	      rejects files which don't begin with an encrypted message.

       --verify
	      Assume that the first argument is a signed file or a detached signature and  verify
	      it  without  generating any output. With no arguments, the signature packet is read
	      from STDIN. If only a sigfile is given,  it  may	be  a  complete  signature  or	a
	      detached	signature,  in	which case the signed stuff is expected in a file without
	      the ".sig" or ".asc" extension.  With more than 1 argument, the first should  be	a
	      detached signature and the remaining files are the signed stuff. To read the signed
	      stuff from STDIN, use '-'' as the second filename.  For security reasons a detached
	      signature  cannot  read  the  signed material from STDIN without denoting it in the
	      above way.

       --multifile
	      This modifies certain other commands to accept multiple files for processing on the
	      command  line or read from STDIN with each filename on a separate line. This allows
	      for many files to be processed at once. --multifile may  currently  be  used  along
	      with  --verify, --encrypt, and --decrypt. Note that --multifile --verify may not be
	      used with detached signatures.

       --verify-files
	      Identical to --multifile --verify.

       --encrypt-files
	      Identical to --multifile --encrypt.

       --decrypt-files
	      Identical to --multifile --decrypt.

       --list-keys

       -k

       --list-public-keys
	      List all keys from the public keyrings, or just the keys given on the command line.
	      -k  is  slightly different from --list-keys in that it allows only for one argument
	      and takes the second argument as the keyring to search.  This is for  command  line
	      compatibility with PGP 2 and has been removed in gpg2.

	      Avoid using the output of this command in scripts or other programs as it is likely
	      to change as GnuPG changes. See --with-colons for a machine-parseable  key  listing
	      command that is appropriate for use in scripts and other programs.

       --list-secret-keys

       -K     List all keys from the secret keyrings, or just the ones given on the command line.
	      A # after the letters sec means that the secret key is not usable (for example,  if
	      it was created via --export-secret-subkeys).

       --list-sigs
	      Same as --list-keys, but the signatures are listed too.

	      For  each  signature  listed,  there are several flags in between the "sig" tag and
	      keyid. These flags give additional information about each signature. From  left  to
	      right, they are the numbers 1-3 for certificate check level (see --ask-cert-level),
	      "L" for a local or non-exportable signature (see --lsign-key), "R" for a nonRevoca-
	      ble  signature (see the --edit-key command "nrsign"), "P" for a signature that con-
	      tains a policy URL (see --cert-policy-url), "N" for a  signature	that  contains	a
	      notation	(see  --cert-notation),  "X"  for  an  eXpired signature (see --ask-cert-
	      expire), and the numbers 1-9 or "T" for 10 and above to  indicate  trust	signature
	      levels (see the --edit-key command "tsign").

       --check-sigs
	      Same  as	--list-sigs,  but the signatures are verified.	Note that for performance
	      reasons the revocation status of a signing key is not shown.

	      The status of the verification is indicated by a flag directly following the  "sig"
	      tag  (and  thus before the flags described above for --list-sigs).  A "!" indicates
	      that the signature has been successfully verified, a "-" denotes	a  bad	signature
	      and  a  "%"  is  used if an error occurred while checking the signature (e.g. a non
	      supported algorithm).

       --fingerprint
	      List all keys (or the specified ones) along with their fingerprints.  This  is  the
	      same  output  as --list-keys but with the additional output of a line with the fin-
	      gerprint. May also be combined with --list-sigs or --check-sigs.	If  this  command
	      is given twice, the fingerprints of all secondary keys are listed too.

       --list-packets
	      List only the sequence of packets. This is mainly useful for debugging.

       --card-edit
	      Present a menu to work with a smartcard. The subcommand "help" provides an overview
	      on available commands. For a detailed description, please see  the  Card	HOWTO  at
	      http://www.gnupg.org/documentation/howtos.html#GnuPG-cardHOWTO .

       --card-status
	      Show the content of the smart card.

       --change-pin
	      Present a menu to allow changing the PIN of a smartcard. This functionality is also
	      available as the subcommand "passwd" with the --card-edit command.

       --delete-key name
	      Remove key from the public keyring. In batch mode either --yes is required  or  the
	      key  must be specified by fingerprint. This is a safeguard against accidental dele-
	      tion of multiple keys.

       --delete-secret-key name
	      Remove key from the secret and public keyring. In batch mode the key must be speci-
	      fied by fingerprint.

       --delete-secret-and-public-key name
	      Same  as	--delete-key,  but  if	a secret key exists, it will be removed first. In
	      batch mode the key must be specified by fingerprint.

       --export
	      Either export all keys from all keyrings (default keyrings and those registered via
	      option  --keyring),  or if at least one name is given, those of the given name. The
	      new keyring is written to STDOUT or to the file given  with  option  --output.  Use
	      together with --armor to mail those keys.

       --send-keys key IDs
	      Similar  to  --export  but sends the keys to a keyserver.  Fingerprints may be used
	      instead of key IDs. Option --keyserver must be used to give the name of  this  key-
	      server.  Don't send your complete keyring to a keyserver --- select only those keys
	      which are new or changed by you.	If no key IDs are given, gpg does nothing.

       --export-secret-keys

       --export-secret-subkeys
	      Same as --export, but exports the secret keys instead.  This is normally	not  very
	      useful  and  a security risk.  The second form of the command has the special prop-
	      erty to render the secret part of the primary key useless; this is a GNU	extension
	      to  OpenPGP  and	other  implementations can not be expected to successfully import
	      such a key.  See the option --simple-sk-checksum if you  want  to  import  such  an
	      exported key with an older OpenPGP implementation.

       --import

       --fast-import
	      Import/merge  keys.  This  adds  the given keys to the keyring. The fast version is
	      currently just a synonym.

	      There are a few other options which control how this command works.   Most  notable
	      here  is	the --import-options merge-only option which does not insert new keys but
	      does only the merging of new signatures, user-IDs and subkeys.

       --recv-keys key IDs
	      Import the keys with the given key IDs from a keyserver. Option --keyserver must be
	      used to give the name of this keyserver.

       --refresh-keys
	      Request  updates from a keyserver for keys that already exist on the local keyring.
	      This is useful for updating a key with the latest signatures, user IDs, etc.  Call-
	      ing this with no arguments will refresh the entire keyring. Option --keyserver must
	      be used to give the name of the keyserver for all keys that do not  have	preferred
	      keyservers set (see --keyserver-options honor-keyserver-url).

       --search-keys names
	      Search  the keyserver for the given names. Multiple names given here will be joined
	      together to create the search string for the keyserver.  Option --keyserver must be
	      used  to give the name of this keyserver.  Keyservers that support different search
	      methods allow using the syntax specified in "How to specify a user ID" below.  Note
	      that  different  keyserver  types  support different search methods. Currently only
	      LDAP supports them all.

       --fetch-keys URIs
	      Retrieve keys located at the specified URIs. Note that different	installations  of
	      GnuPG may support different protocols (HTTP, FTP, LDAP, etc.)

       --update-trustdb
	      Do  trust  database maintenance. This command iterates over all keys and builds the
	      Web of Trust. This is an interactive command because it may have	to  ask  for  the
	      "ownertrust"  values  for  keys.	The user has to give an estimation of how far she
	      trusts the owner of the displayed key to correctly certify (sign) other keys. GnuPG
	      only  asks for the ownertrust value if it has not yet been assigned to a key. Using
	      the --edit-key menu, the assigned value can be changed at any time.

       --check-trustdb
	      Do trust database maintenance without user interaction. From time to time the trust
	      database	must  be  updated  so  that  expired keys or signatures and the resulting
	      changes in the Web of Trust can be tracked. Normally,  GnuPG  will  calculate  when
	      this  is	required  and  do it automatically unless --no-auto-check-trustdb is set.
	      This command can be used to force a trust database check at any time. The  process-
	      ing  is  identical  to  that  of	--update-trustdb but it skips keys with a not yet
	      defined "ownertrust".

	      For use with cron jobs, this command can be used together  with  --batch	in  which
	      case  the  trust	database  check is done only if a check is needed. To force a run
	      even in batch mode add the option --yes.

       --export-ownertrust
	      Send the ownertrust values to STDOUT. This is useful for backup purposes	as  these
	      values are the only ones which can't be re-created from a corrupted trustdb.  Exam-
	      ple:
		  gpg --export-ownertrust > otrust.txt

       --import-ownertrust
	      Update the trustdb with the ownertrust values stored in  files  (or  STDIN  if  not
	      given); existing values will be overwritten.  In case of a severely damaged trustdb
	      and if you have a recent	backup	of  the  ownertrust  values  (e.g.  in	the  file
	      `otrust.txt', you may re-create the trustdb using these commands:
		  cd ~/.gnupg
		  rm trustdb.gpg
		  gpg --import-ownertrust < otrust.txt

       --rebuild-keydb-caches
	      When  updating  from  version  1.0.6 to 1.0.7 this command should be used to create
	      signature caches in the keyring. It might be handy in other situations too.

       --print-md algo

       --print-mds
	      Print message digest of algorithm ALGO for all given files or STDIN.  With the sec-
	      ond  form  (or  a  deprecated "*" as algo) digests for all available algorithms are
	      printed.

       --gen-random 0|1|2 count
	      Emit count random bytes of the given quality level 0, 1 or 2. If count is not given
	      or zero, an endless sequence of random bytes will be emitted.  If used with --armor
	      the output will be base64 encoded.  PLEASE, don't use this command unless you  know
	      what you are doing; it may remove precious entropy from the system!

       --gen-prime mode bits
	      Use the source, Luke :-). The output format is still subject to change.

       --enarmor

       --dearmor
	      Pack  or	unpack	an  arbitrary  input into/from an OpenPGP ASCII armor.	This is a
	      GnuPG extension to OpenPGP and in general not very useful.

   How to manage your keys

       This section explains the main commands for key management

       --gen-key
	      Generate a new key pair. This command is normally only used interactively.

	      There is an experimental feature which allows you to create keys in batch mode. See
	      the file `doc/DETAILS' in the source distribution on how to use this.

       --gen-revoke name
	      Generate	a  revocation  certificate  for the complete key. To revoke a subkey or a
	      signature, use the --edit command.

       --desig-revoke name
	      Generate a designated revocation certificate for a key. This allows  a  user  (with
	      the permission of the keyholder) to revoke someone else's key.

       --edit-key
	      Present  a  menu	which enables you to do most of the key management related tasks.
	      It expects the specification of a key on the command line.

	      uid n  Toggle selection of user ID or photographic user ID with index n.	Use *  to
		     select all and 0 to deselect all.

	      key n  Toggle selection of subkey with index n.  Use * to select all and 0 to dese-
		     lect all.

	      sign   Make a signature on key of user name If the key is not  yet  signed  by  the
		     default user (or the users given with -u), the program displays the informa-
		     tion of the key again, together with its fingerprint  and	asks  whether  it
		     should be signed. This question is repeated for all users specified with -u.

	      lsign  Same as "sign" but the signature is marked as non-exportable and will there-
		     fore never be used by others. This may be used to make keys  valid  only  in
		     the local environment.

	      nrsign Same  as  "sign" but the signature is marked as non-revocable and can there-
		     fore never be revoked.

	      tsign  Make a trust signature. This is a signature that  combines  the  notions  of
		     certification  (like  a regular signature), and trust (like the "trust" com-
		     mand). It is generally only useful in distinct communities or groups.

	      Note that "l" (for local / non-exportable), "nr" (for non-revocable, and	"t"  (for
	      trust) may be freely mixed and prefixed to "sign" to create a signature of any type
	      desired.

	      delsig Delete a signature. Note that it is not possible  to  retract  a  signature,
		     once it has been send to the public (i.e. to a keyserver).  In that case you
		     better use revsig.

	      revsig Revoke a signature. For every signature which has been generated by  one  of
		     the  secret keys, GnuPG asks whether a revocation certificate should be gen-
		     erated.

	      check  Check the signatures on all selected user IDs.

	      adduid Create an additional user ID.

	      addphoto
		     Create a photographic user ID. This will prompt for a JPEG file that will be
		     embedded  into the user ID. Note that a very large JPEG will make for a very
		     large key. Also note that some programs will  display  your  JPEG	unchanged
		     (GnuPG), and some programs will scale it to fit in a dialog box (PGP).

	      showphoto
		     Display the selected photographic user ID.

	      deluid Delete  a	user ID or photographic user ID.  Note that it is not possible to
		     retract a user id, once it has been send to  the  public  (i.e.  to  a  key-
		     server).  In that case you better use revuid.

	      revuid Revoke a user ID or photographic user ID.

	      primary
		     Flag  the	current  user  id as the primary one, removes the primary user id
		     flag from all other user ids and sets the timestamp of  all  affected  self-
		     signatures  one  second  ahead. Note that setting a photo user ID as primary
		     makes it primary over other photo user IDs, and setting a regular user ID as
		     primary makes it primary over other regular user IDs.

	      keyserver
		     Set  a  preferred	keyserver for the specified user ID(s). This allows other
		     users to know where you prefer they get  your  key  from.	See  --keyserver-
		     options  honor-keyserver-url for more on how this works.  Setting a value of
		     "none" removes an existing preferred keyserver.

	      notation
		     Set a name=value notation for the specified user ID(s). See  --cert-notation
		     for more on how this works. Setting a value of "none" removes all notations,
		     setting a notation prefixed with a minus sign (-) removes that notation, and
		     setting  a  notation  name  (without  the =value) prefixed with a minus sign
		     removes all notations with that name.

	      pref   List preferences from the selected user ID. This shows  the  actual  prefer-
		     ences, without including any implied preferences.

	      showpref
		     More  verbose  preferences  listing for the selected user ID. This shows the
		     preferences in effect by including the implied preferences of 3DES (cipher),
		     SHA-1  (digest),  and  Uncompressed  (compression)  if  they are not already
		     included in the preference list. In addition, the	preferred  keyserver  and
		     signature notations (if any) are shown.

	      setpref string
		     Set the list of user ID preferences to string for all (or just the selected)
		     user IDs. Calling setpref with no arguments sets the preference list to  the
		     default  (either built-in or set via --default-preference-list), and calling
		     setpref with "none" as the argument sets an empty preference list.  Use  gpg
		     --version	to  get  a  list of available algorithms. Note that while you can
		     change the preferences on an attribute user ID (aka "photo ID"), GnuPG  does
		     not select keys via attribute user IDs so these preferences will not be used
		     by GnuPG.

		     When setting preferences, you should list the algorithms in the order  which
		     you'd  like  to  see  them used by someone else when encrypting a message to
		     your key.	If you don't include 3DES, it will be automatically added at  the
		     end.   Note  that	there are many factors that go into choosing an algorithm
		     (for example, your key may not be the only recipient),  and  so  the  remote
		     OpenPGP  application  being  used	to send to you may or may not follow your
		     exact chosen order for a given message.  It will, however,  only  choose  an
		     algorithm	that  is  present  on the preference list of every recipient key.
		     See also the INTEROPERABILITY WITH OTHER OPENPGP PROGRAMS section below.

	      addkey Add a subkey to this key.

	      addcardkey
		     Generate a subkey on a card and add it to this key.

	      keytocard
		     Transfer the selected secret subkey (or the primary key  if  no  subkey  has
		     been  selected)  to  a  smartcard.  The  secret  key  in the keyring will be
		     replaced by a stub if the key could be stored successfully on the	card  and
		     you use the save command later. Only certain key types may be transferred to
		     the card. A sub menu allows you to select on what card  to  store	the  key.
		     Note  that  it  is  not possible to get that key back from the card - if the
		     card gets broken your secret key will be lost unless you have a backup some-
		     where.

	      bkuptocard file
		     Restore  the  given  file	to  a card. This command may be used to restore a
		     backup key (as generated during card  initialization)  to	a  new	card.  In
		     almost  all  cases this will be the encryption key. You should use this com-
		     mand only with the corresponding public key and  make  sure  that	the  file
		     given  as argument is indeed the backup to restore. You should then select 2
		     to restore as encryption  key.   You  will  first	be  asked  to  enter  the
		     passphrase of the backup key and then for the Admin PIN of the card.

	      delkey Remove  a	subkey (secondart key). Note that it is not possible to retract a
		     subkey, once it has been send to the public (i.e. to a keyserver).  In  that
		     case you better use revkey.

	      revkey Revoke a subkey.

	      expire Change the key or subkey expiration time. If a subkey is selected, the expi-
		     ration time of this subkey will be changed. With no selection, the key expi-
		     ration of the primary key is changed.

	      trust  Change  the owner trust value for the key. This updates the trust-db immedi-
		     ately and no save is required.

	      disable

	      enable Disable or enable an entire key. A disabled key can not normally be used for
		     encryption.

	      addrevoker
		     Add a designated revoker to the key. This takes one optional argument: "sen-
		     sitive". If a designated revoker is marked as  sensitive,	it  will  not  be
		     exported by default (see export-options).

	      passwd Change the passphrase of the secret key.

	      toggle Toggle between public and secret key listing.

	      clean  Compact  (by removing all signatures except the selfsig) any user ID that is
		     no longer usable (e.g. revoked, or expired).  Then,  remove  any  signatures
		     that  are	not usable by the trust calculations.  Specifically, this removes
		     any signature that does not validate, any signature that is superseded by	a
		     later  signature, revoked signatures, and signatures issued by keys that are
		     not present on the keyring.

	      minimize
		     Make the key as small as possible. This removes  all  signatures  from  each
		     user ID except for the most recent self-signature.

	      cross-certify
		     Add cross-certification signatures to signing subkeys that may not currently
		     have them. Cross-certification signatures protect against	a  subtle  attack
		     against  signing  subkeys.  See --require-cross-certification.  All new keys
		     generated have this signature by default, so this option is only  useful  to
		     bring older keys up to date.

	      save   Save all changes to the key rings and quit.

	      quit   Quit the program without updating the key rings.

	      The  listing  shows you the key with its secondary keys and all user ids.  The pri-
	      mary user id is indicated by a dot, and selected keys or user ids are indicated  by
	      an  asterisk.   The trust value is displayed with the primary key: the first is the
	      assigned owner trust and the second is the calculated trust value. Letters are used
	      for the values:

	      -      No ownertrust assigned / not yet calculated.

	      e      Trust calculation has failed; probably due to an expired key.

	      q      Not enough information for calculation.

	      n      Never trust this key.

	      m      Marginally trusted.

	      f      Fully trusted.

	      u      Ultimately trusted.

       --sign-key name
	      Signs  a public key with your secret key. This is a shortcut version of the subcom-
	      mand "sign" from --edit.

       --lsign-key name
	      Signs a public key with your secret key but marks it as non-exportable. This  is	a
	      shortcut version of the subcommand "lsign" from --edit-key.


OPTIONS
       gpg  features  a bunch of options to control the exact behaviour and to change the default
       configuration.

       Long options can be put in an options file  (default  "~/.gnupg/gpg.conf").  Short  option
       names  will  not work - for example, "armor" is a valid option for the options file, while
       "a" is not. Do not write the 2 dashes, but simply the name of the option and any  required
       arguments.  Lines  with	a  hash ('#') as the first non-white-space character are ignored.
       Commands may be put in this file too, but that is not generally useful as the command will
       execute automatically with every execution of gpg.

       Please  remember that option parsing stops as soon as a non-option is encountered, you can
       explicitly stop parsing by using the special option --.

   How to change the configuration

       These options are used to change the configuration and are usually  found  in  the  option
       file.

       --default-key name
	      Use  name  as the default key to sign with. If this option is not used, the default
	      key is the first key found in the secret keyring.  Note  that  -u  or  --local-user
	      overrides this option.

       --default-recipient name
	      Use  name  as  default recipient if option --recipient is not used and don't ask if
	      this is a valid one. name must be non-empty.

       --default-recipient-self
	      Use the default key as default recipient if option  --recipient  is  not	used  and
	      don't  ask if this is a valid one. The default key is the first one from the secret
	      keyring or the one set with --default-key.

       --no-default-recipient
	      Reset --default-recipient and --default-recipient-self.

       -v, --verbose
	      Give more information during processing. If used twice, the input data is listed in
	      detail.

       --no-verbose
	      Reset verbose level to 0.

       -q, --quiet
	      Try to be as quiet as possible.

       --batch

       --no-batch
	      Use batch mode.  Never ask, do not allow interactive commands.  --no-batch disables
	      this option.  Note that even with a filename given on the command line,  gpg  might
	      still  need  to  read  from STDIN (in particular if gpg figures that the input is a
	      detached signature and no data file has been specified).	Thus if you do	not  want
	      to feed data via STDIN, you should connect STDIN to `/dev/null'.

       --no-tty
	      Make  sure  that	the  TTY (terminal) is never used for any output.  This option is
	      needed in some cases because GnuPG sometimes prints warnings to  the  TTY  even  if
	      --batch is used.

       --yes  Assume "yes" on most questions.

       --no   Assume "no" on most questions.

       --list-options parameters
	      This is a space or comma delimited string that gives options used when listing keys
	      and signatures (that  is,  --list-keys,  --list-sigs,  --list-public-keys,  --list-
	      secret-keys,  and  the  --edit-key functions).  Options can be prepended with a no-
	      (after the two dashes) to give the opposite meaning.  The options are:

	      show-photos
		     Causes --list-keys, --list-sigs, --list-public-keys, and  --list-secret-keys
		     to  display  any  photo  IDs  attached to the key.  Defaults to no. See also
		     --photo-viewer.

	      show-policy-urls
		     Show policy URLs in the --list-sigs or --check-sigs listings.   Defaults  to
		     no.

	      show-notations

	      show-std-notations

	      show-user-notations
		     Show  all, IETF standard, or user-defined signature notations in the --list-
		     sigs or --check-sigs listings. Defaults to no.

	      show-keyserver-urls

		     Show any preferred keyserver URL in the --list-sigs  or  --check-sigs  list-
		     ings. Defaults to no.

	      show-uid-validity
		     Display  the  calculated validity of user IDs during key listings.  Defaults
		     to no.

	      show-unusable-uids
		     Show revoked and expired user IDs in key listings. Defaults to no.

	      show-unusable-subkeys
		     Show revoked and expired subkeys in key listings. Defaults to no.

	      show-keyring
		     Display the keyring name at the head of key listings to show which keyring a
		     given key resides on. Defaults to no.

	      show-sig-expire
		     Show  signature expiration dates (if any) during --list-sigs or --check-sigs
		     listings. Defaults to no.

	      show-sig-subpackets
		     Include signature subpackets in the key listing. This  option  can  take  an
		     optional  argument list of the subpackets to list. If no argument is passed,
		     list all subpackets. Defaults to no. This option  is  only  meaningful  when
		     using --with-colons along with --list-sigs or --check-sigs.

       --verify-options parameters
	      This  is	a  space or comma delimited string that gives options used when verifying
	      signatures. Options can be prepended with a `no-' to give the opposite meaning. The
	      options are:

	      show-photos
		     Display  any  photo  IDs  present	on  the  key  that  issued the signature.
		     Defaults to no. See also --photo-viewer.

	      show-policy-urls
		     Show policy URLs in the signature being verified. Defaults to no.

	      show-notations

	      show-std-notations

	      show-user-notations
		     Show all, IETF standard, or user-defined signature notations in  the  signa-
		     ture being verified. Defaults to IETF standard.

	      show-keyserver-urls
		     Show  any preferred keyserver URL in the signature being verified.  Defaults
		     to no.

	      show-uid-validity
		     Display the calculated validity of the user IDs on the key that  issued  the
		     signature. Defaults to no.

	      show-unusable-uids
		     Show  revoked  and expired user IDs during signature verification.  Defaults
		     to no.

	      show-primary-uid-only
		     Show only the primary user ID during signature verification.   That  is  all
		     the  AKA lines as well as photo Ids are not shown with the signature verifi-
		     cation status.

	      pka-lookups
		     Enable PKA lookups to verify sender addresses. Note that  PKA  is	based  on
		     DNS,  and	so enabling this option may disclose information on when and what
		     signatures are verified or to whom data is encrypted. This is similar to the
		     "web bug" described for the auto-key-retrieve feature.

	      pka-trust-increase
		     Raise  the  trust in a signature to full if the signature passes PKA valida-
		     tion. This option is only meaningful if pka-lookups is set.

       --enable-dsa2

       --disable-dsa2
	      Enable hash truncation for all DSA keys even for old DSA Keys up to 1024 bit.  This
	      is  also	the  default  with  --openpgp.	 Note  that  older versions of GnuPG also
	      required this flag to allow the generation of DSA larger than 1024 bit.

       --photo-viewer string
	      This is the command line that should be run to  view  a  photo  ID.  "%i"  will  be
	      expanded	to  a  filename containing the photo. "%I" does the same, except the file
	      will not be deleted once the viewer exits.  Other flags are "%k" for  the  key  ID,
	      "%K"  for  the long key ID, "%f" for the key fingerprint, "%t" for the extension of
	      the  image  type	(e.g.  "jpg"),	"%T"  for  the	MIME  type  of	the  image  (e.g.
	      "image/jpeg"), "%v" for the single-character calculated validity of the image being
	      viewed (e.g. "f"), "%V" for the calculated validity as a string (e.g.  "full"), and
	      "%%"  for  an  actual percent sign. If neither %i or %I are present, then the photo
	      will be supplied to the viewer on standard input.

	      The default viewer is "xloadimage -fork -quiet -title  'KeyID  0x%k'  STDIN".  Note
	      that  if your image viewer program is not secure, then executing it from GnuPG does
	      not make it secure.

       --exec-path string
	      Sets a list of directories to search for photo viewers and  keyserver  helpers.  If
	      not  provided,  keyserver  helpers use the compiled-in default directory, and photo
	      viewers use the $PATH environment variable.  Note, that on W32 system this value is
	      ignored when searching for keyserver helpers.

       --keyring file
	      Add  file to the current list of keyrings. If file begins with a tilde and a slash,
	      these are replaced by the $HOME directory. If  the  filename  does  not  contain	a
	      slash,  it is assumed to be in the GnuPG home directory ("~/.gnupg" if --homedir or
	      $GNUPGHOME is not used).

	      Note that this adds a keyring to the current list. If the  intent  is  to  use  the
	      specified keyring alone, use --keyring along with --no-default-keyring.

       --secret-keyring file
	      Same as --keyring but for the secret keyrings.

       --primary-keyring file
	      Designate  file  as the primary public keyring. This means that newly imported keys
	      (via --import or keyserver --recv-from) will go to this keyring.

       --trustdb-name file
	      Use file instead of the default trustdb. If file begins with a tilde and	a  slash,
	      these  are  replaced  by	the  $HOME  directory. If the filename does not contain a
	      slash, it is assumed to be in the GnuPG home directory (`~/.gnupg' if --homedir  or
	      $GNUPGHOME is not used).

       --homedir dir
	      Set  the	name  of  the home directory to dir. If this option is not used, the home
	      directory defaults to `~/.gnupg'.  It is only recognized when given on the  command
	      line.  It also overrides any home directory stated through the environment variable
	      `GNUPGHOME' or  (on  W32	systems)  by  means  of  the  Registry	entry  HKCU\Soft-
	      ware\GNU\GnuPG:HomeDir.

       --pcsc-driver file
	      Use  file to access the smartcard reader. The current default is `libpcsclite.so.1'
	      for GLIBC based systems, `/System/Library/Frameworks/PCSC.framework/PCSC'  for  MAC
	      OS X, `winscard.dll' for Windows and `libpcsclite.so' for other systems.

       --disable-ccid
	      Disable the integrated support for CCID compliant readers. This allows to fall back
	      to one of the other drivers even if the internal CCID driver can handle the reader.
	      Note, that CCID support is only available if libusb was available at build time.

       --reader-port number_or_string
	      This  option  may  be  used  to specify the port of the card terminal. A value of 0
	      refers to the first serial device; add 32768 to access USB devices. The default  is
	      32768  (first  USB device). PC/SC or CCID readers might need a string here; run the
	      program in verbose mode to get a list of available readers. The default is then the
	      first reader found.

       --display-charset name
	      Set  the	name  of  the native character set. This is used to convert some informa-
	      tional strings like user IDs to the proper UTF-8	encoding.   Note  that	this  has
	      nothing  to do with the character set of data to be encrypted or signed; GnuPG does
	      not recode user-supplied data. If this option is not used,  the  default	character
	      set  is determined from the current locale. A verbosity level of 3 shows the chosen
	      set.  Valid values for name are:

	      iso-8859-1
		     This is the Latin 1 set.

	      iso-8859-2
		     The Latin 2 set.

	      iso-8859-15
		     This is currently an alias for the Latin 1 set.

	      koi8-r The usual Russian set (rfc1489).

	      utf-8  Bypass all translations and assume that the OS uses native UTF-8 encoding.

       --utf8-strings

       --no-utf8-strings
	      Assume that command line arguments are given as UTF8 strings.  The  default  (--no-
	      utf8-strings) is to assume that arguments are encoded in the character set as spec-
	      ified by --display-charset. These options  affect  all  following  arguments.  Both
	      options may be used multiple times.

       --options file
	      Read options from file and do not try to read them from the default options file in
	      the homedir (see --homedir). This option is ignored if used in an options file.

       --no-options
	      Shortcut for --options /dev/null. This option is detected before an attempt to open
	      an  option  file.  Using this option will also prevent the creation of a `~/.gnupg'
	      homedir.

       -z n

       --compress-level n

       --bzip2-compress-level n
	      Set compression level to n for the ZIP and ZLIB compression algorithms. The default
	      is  to  use  the	default compression level of zlib (normally 6). --bzip2-compress-
	      level sets the compression level for the BZIP2 compression algorithm (defaulting to
	      6  as  well).  This  is a different option from --compress-level since BZIP2 uses a
	      significant amount of memory for each additional compression level.  -z sets  both.
	      A value of 0 for n disables compression.

       --bzip2-decompress-lowmem
	      Use  a  different  decompression	method for BZIP2 compressed files. This alternate
	      method uses a bit more than half the memory, but also runs at half the speed.  This
	      is  useful under extreme low memory circumstances when the file was originally com-
	      pressed at a high --bzip2-compress-level.

       --mangle-dos-filenames

       --no-mangle-dos-filenames
	      Older version of Windows cannot handle filenames with more than one dot.	--mangle-
	      dos-filenames causes GnuPG to replace (rather than add to) the extension of an out-
	      put filename to avoid this problem. This option is off by default and has no effect
	      on non-Windows platforms.

       --ask-cert-level

       --no-ask-cert-level
	      When  making  a  key signature, prompt for a certification level. If this option is
	      not specified, the certification level used is set  via  --default-cert-level.  See
	      --default-cert-level  for information on the specific levels and how they are used.
	      --no-ask-cert-level disables this option. This option defaults to no.

       --default-cert-level n
	      The default to use for the check level when signing a key.

	      0 means you make no particular claim as to how carefully you verified the key.

	      1 means you believe the key is owned by the person who claims to	own  it  but  you
	      could not, or did not verify the key at all. This is useful for a "persona" verifi-
	      cation, where you sign the key of a pseudonymous user.

	      2 means you did casual verification of the key. For example, this could  mean  that
	      you  verified that the key fingerprint and checked the user ID on the key against a
	      photo ID.

	      3 means you did extensive verification of the key. For  example,	this  could  mean
	      that you verified the key fingerprint with the owner of the key in person, and that
	      you checked, by means of a hard to forge document with a photo ID (such as a  pass-
	      port)  that  the	name of the key owner matches the name in the user ID on the key,
	      and finally that you verified (by exchange of email) that the email address on  the
	      key belongs to the key owner.

	      Note  that  the examples given above for levels 2 and 3 are just that: examples. In
	      the end, it is up to you to decide just what "casual" and "extensive" mean to you.

	      This option defaults to 0 (no particular claim).

       --min-cert-level
	      When building the trust database, treat any signatures with a  certification  level
	      below  this  as  invalid.  Defaults to 2, which disregards level 1 signatures. Note
	      that level 0 "no particular claim" signatures are always accepted.

       --trusted-key long key ID
	      Assume that the specified key (which must be given as a full 8 byte key ID)  is  as
	      trustworthy as one of your own secret keys. This option is useful if you don't want
	      to keep your secret keys (or one of them) online but still want to be able to check
	      the validity of a given recipient's or signator's key.

       --trust-model pgp|classic|direct|always|auto
	      Set what trust model GnuPG should follow. The models are:

	      pgp    This  is  the Web of Trust combined with trust signatures as used in PGP 5.x
		     and later. This is the default trust model when creating a new  trust  data-
		     base.

	      classic
		     This is the standard Web of Trust as used in PGP 2.x and earlier.

	      direct Key  validity  is set directly by the user and not calculated via the Web of
		     Trust.

	      always Skip key validation and assume that used keys are always fully trusted.  You
		     generally	won't  use  this  unless  you  are using some external validation
		     scheme. This option also suppresses the "[uncertain]" tag printed with  sig-
		     nature  checks  when  there  is no evidence that the user ID is bound to the
		     key.

	      auto   Select the trust model depending on whatever  the	internal  trust  database
		     says. This is the default model if such a database already exists.

       --auto-key-locate parameters

       --no-auto-key-locate
	      GnuPG  can automatically locate and retrieve keys as needed using this option. This
	      happens when encrypting to an email address (in the "user@example.com"  form),  and
	      there  are  no  user@example.com	keys on the local keyring.  This option takes any
	      number of the following mechanisms, in the order they are to be tried:

	      cert   Locate a key using DNS CERT, as specified in rfc4398.

	      pka    Locate a key using DNS PKA.

	      ldap   Using DNS Service Discovery, check the domain in question for any LDAP  key-
		     servers to use.  If this fails, attempt to locate the key using the PGP Uni-
		     versal method of checking 'ldap://keys.(thedomain)''.

	      keyserver
		     Locate a key using whatever  keyserver  is  defined  using  the  --keyserver
		     option.

	      keyserver-URL
		     In  addition,  a keyserver URL as used in the --keyserver option may be used
		     here to query that particular keyserver.

	      local  Locate the key using the local keyrings.  This mechanism  allows  to  select
		     the order a local key lookup is done.  Thus using '--auto-key-locate local''
		     is identical to --no-auto-key-locate.

	      nodefault
		     This flag disables the standard local key lookup, done  before  any  of  the
		     mechanisms defined by the --auto-key-locate are tried.  The position of this
		     mechanism in the list does not matter.  It is not required if local is  also
		     used.

       --keyid-format short|0xshort|long|0xlong
	      Select  how  to  display	key  IDs.  "short" is the traditional 8-character key ID.
	      "long" is the more accurate (but less convenient) 16-character key ID. Add an  "0x"
	      to either to include an "0x" at the beginning of the key ID, as in 0x99242560.

       --keyserver name
	      Use  name  as your keyserver. This is the server that --recv-keys, --send-keys, and
	      --search-keys will communicate with to receive keys from, send keys to, and  search
	      for keys on. The format of the name is a URI: `scheme:[//]keyservername[:port]' The
	      scheme is the type of keyserver: "hkp" for the  HTTP  (or  compatible)  keyservers,
	      "ldap"  for  the	LDAP  keyservers, or "mailto" for the Graff email keyserver. Note
	      that your particular installation of GnuPG may have other keyserver types available
	      as well. Keyserver schemes are case-insensitive. After the keyserver name, optional
	      keyserver configuration options may be provided. These are the same as  the  global
	      --keyserver-options from below, but apply only to this particular keyserver.

	      Most  keyservers synchronize with each other, so there is generally no need to send
	      keys to more than one server. The keyserver hkp://keys.gnupg.net uses  round  robin
	      DNS to give a different keyserver each time you use it.

       --keyserver-options name=value1
	      This  is	a  space  or comma delimited string that gives options for the keyserver.
	      Options can be prefixed with a `no-' to give the opposite  meaning.  Valid  import-
	      options  or  export-options may be used here as well to apply to importing (--recv-
	      key) or exporting (--send-key) a key from a keyserver. While not	all  options  are
	      available for all keyserver types, some common options are:

	      include-revoked
		     When searching for a key with --search-keys, include keys that are marked on
		     the keyserver as revoked. Note that not all keyservers differentiate between
		     revoked  and unrevoked keys, and for such keyservers this option is meaning-
		     less. Note also that most keyservers do not have cryptographic  verification
		     of  key  revocations,  and so turning this option off may result in skipping
		     keys that are incorrectly marked as revoked.

	      include-disabled
		     When searching for a key with --search-keys, include keys that are marked on
		     the  keyserver  as disabled. Note that this option is not used with HKP key-
		     servers.

	      auto-key-retrieve
		     This option enables the automatic retrieving of keys from a  keyserver  when
		     verifying signatures made by keys that are not on the local keyring.

		     Note  that  this option makes a "web bug" like behavior possible.	Keyserver
		     operators can see which keys you request, so by sending you a message signed
		     by  a  brand  new	key  (which  you  naturally  will  not have on your local
		     keyring), the operator can tell both your IP address and the time	when  you
		     verified the signature.

	      honor-keyserver-url
		     When  using --refresh-keys, if the key in question has a preferred keyserver
		     URL, then use that preferred keyserver to refresh the key from. In addition,
		     if  auto-key-retrieve  is	set,  and the signature being verified has a pre-
		     ferred keyserver URL, then use that preferred keyserver  to  fetch  the  key
		     from. Defaults to yes.

	      honor-pka-record
		     If  auto-key-retrieve  is	set,  and  the signature being verified has a PKA
		     record, then use the PKA information to fetch the key. Defaults to yes.

	      include-subkeys
		     When receiving a key, include subkeys as potential targets. Note  that  this
		     option  is  not  used with HKP keyservers, as they do not support retrieving
		     keys by subkey id.

	      use-temp-files
		     On most Unix-like platforms, GnuPG communicates with  the	keyserver  helper
		     program  via  pipes,  which is the most efficient method. This option forces
		     GnuPG to use temporary files to communicate.  On  some  platforms	(such  as
		     Win32 and RISC OS), this option is always enabled.

	      keep-temp-files
		     If  using	`use-temp-files',  do not delete the temp files after using them.
		     This option is useful to learn the keyserver communication protocol by read-
		     ing the temporary files.

	      verbose
		     Tell  the	keyserver  helper  program to be more verbose. This option can be
		     repeated multiple times to increase the verbosity level.

	      timeout
		     Tell the keyserver helper program how long (in seconds) to try and perform a
		     keyserver	action before giving up. Note that performing multiple actions at
		     the same time uses  this  timeout	value  per  action.   For  example,  when
		     retrieving  multiple keys via --recv-keys, the timeout applies separately to
		     each key retrieval, and not to the --recv-keys command as a whole.  Defaults
		     to 30 seconds.

	      http-proxy=value
		     Set  the  proxy  to  use  for  HTTP  and HKP keyservers.  This overrides the
		     "http_proxy" environment variable, if any.

	      max-cert-size
		     When retrieving a key via DNS CERT,  only	accept	keys  up  to  this  size.
		     Defaults to 16384 bytes.

	      debug  Turn on debug output in the keyserver helper program.  Note that the details
		     of debug output depends on which keyserver helper program is being used, and
		     in  turn, on any libraries that the keyserver helper program uses internally
		     (libcurl, openldap, etc).

	      check-cert
		     Enable certificate checking if the  keyserver  presents  one  (for  hkps  or
		     ldaps).  Defaults to on.

	      ca-cert-file
		     Provide  a certificate store to override the system default.  Only necessary
		     if check-cert is enabled, and the keyserver is using a certificate  that  is
		     not present in a system default certificate list.

		     Note  that  depending  on the SSL library that the keyserver helper is built
		     with, this may actually be a directory or a file.

       --completes-needed n
	      Number of completely trusted users to introduce a new key signer (defaults to 1).

       --marginals-needed n
	      Number of marginally trusted users to introduce a new key signer (defaults to 3)

       --max-cert-depth n
	      Maximum depth of a certification chain (default is 5).

       --simple-sk-checksum
	      Secret keys are integrity protected by using a SHA-1 checksum. This method is  part
	      of the upcoming enhanced OpenPGP specification but GnuPG already uses it as a coun-
	      termeasure against certain attacks.  Old applications  don't  understand	this  new
	      format,  so this option may be used to switch back to the old behaviour. Using this
	      option bears a security risk. Note that using this option only  takes  effect  when
	      the secret key is encrypted - the simplest way to make this happen is to change the
	      passphrase on the key (even changing it to the same value is acceptable).

       --no-sig-cache
	      Do not cache the verification status of key signatures.  Caching gives a much  bet-
	      ter  performance	in key listings. However, if you suspect that your public keyring
	      is not save against write modifications, you can use this  option  to  disable  the
	      caching.	It  probably does not make sense to disable it because all kind of damage
	      can be done if someone else has write access to your public keyring.

       --no-sig-create-check
	      GnuPG normally verifies each signature right after creation to protect against bugs
	      and hardware malfunctions which could leak out bits from the secret key. This extra
	      verification needs some time (about 115% for DSA keys), and so this option  can  be
	      used  to	disable  it.   However, due to the fact that the signature creation needs
	      manual interaction, this performance penalty does not matter in most settings.

       --auto-check-trustdb

       --no-auto-check-trustdb
	      If GnuPG feels that its information about the Web of Trust has to  be  updated,  it
	      automatically runs the --check-trustdb command internally.  This may be a time con-
	      suming process. --no-auto-check-trustdb disables this option.

       --use-agent

       --no-use-agent
	      Try to use the GnuPG-Agent.  With this option, GnuPG first tries to connect to  the
	      agent before it asks for a passphrase. --no-use-agent disables this option.

       --gpg-agent-info
	      Override the value of the environment variable 'GPG_AGENT_INFO''. This is only used
	      when --use-agent has been given.	Given that this option is  not	anymore  used  by
	      gpg2, it should be avoided if possible.

       --lock-once
	      Lock  the  databases the first time a lock is requested and do not release the lock
	      until the process terminates.

       --lock-multiple
	      Release the locks every time a lock is no longer needed. Use  this  to  override	a
	      previous --lock-once from a config file.

       --lock-never
	      Disable  locking entirely. This option should be used only in very special environ-
	      ments, where it can be assured that only one process is accessing  those	files.	A
	      bootable	floppy	with  a  stand-alone  encryption  system  will probably use this.
	      Improper usage of this option may lead to data and key corruption.

       --exit-on-status-write-error
	      This option will cause write errors on the status FD to immediately  terminate  the
	      process.	That  should in fact be the default but it never worked this way and thus
	      we need an option to enable this, so that the change won't break applications which
	      close  their  end  of a status fd connected pipe too early. Using this option along
	      with --enable-progress-filter may be used to cleanly cancel long running gpg opera-
	      tions.

       --limit-card-insert-tries n
	      With  n greater than 0 the number of prompts asking to insert a smartcard gets lim-
	      ited to N-1. Thus with a value of 1 gpg won't at all ask to insert a card  if  none
	      has  been  inserted  at startup. This option is useful in the configuration file in
	      case an application does not know about the smartcard support and waits ad  infini-
	      tum for an inserted card.

       --no-random-seed-file
	      GnuPG  uses  a file to store its internal random pool over invocations.  This makes
	      random generation faster; however sometimes write operations are not desired.  This
	      option can be used to achieve that with the cost of slower random generation.

       --no-greeting
	      Suppress the initial copyright message.

       --no-secmem-warning
	      Suppress the warning about "using insecure memory".

       --no-permission-warning
	      Suppress	the warning about unsafe file and home directory (--homedir) permissions.
	      Note that the permission checks that GnuPG performs are not intended to be authori-
	      tative,  but  rather  they simply warn about certain common permission problems. Do
	      not assume that the lack of a warning means that your system is secure.

	      Note that the warning for unsafe --homedir permissions cannot be suppressed in  the
	      gpg.conf	file, as this would allow an attacker to place an unsafe gpg.conf file in
	      place, and use this file to suppress warnings about itself. The  --homedir  permis-
	      sions warning may only be suppressed on the command line.

       --no-mdc-warning
	      Suppress the warning about missing MDC integrity protection.

       --require-secmem

       --no-require-secmem
	      Refuse to run if GnuPG cannot get secure memory. Defaults to no (i.e. run, but give
	      a warning).

       --require-cross-certification

       --no-require-cross-certification
	      When verifying a signature made from a subkey, ensure that the cross  certification
	      "back  signature" on the subkey is present and valid.  This protects against a sub-
	      tle attack against subkeys that can sign.  Defaults  to  --require-cross-certifica-
	      tion for gpg.

       --expert

       --no-expert
	      Allow  the user to do certain nonsensical or "silly" things like signing an expired
	      or revoked key, or certain potentially incompatible things like generating  unusual
	      key types. This also disables certain warning messages about potentially incompati-
	      ble actions. As the name implies, this option is for experts  only.  If  you  don't
	      fully  understand  the  implications  of	what it allows you to do, leave this off.
	      --no-expert disables this option.

   Key related options

       --recipient name

       -r     Encrypt for user id name. If this option or --hidden-recipient  is  not  specified,
	      GnuPG asks for the user-id unless --default-recipient is given.

       --hidden-recipient name

       -R     Encrypt for user ID name, but hide the key ID of this user's key. This option helps
	      to hide the receiver of the message and is a limited countermeasure against traffic
	      analysis.  If  this option or --recipient is not specified, GnuPG asks for the user
	      ID unless --default-recipient is given.

       --encrypt-to name
	      Same as --recipient but this one is intended for use in the options file and may be
	      used  with  your own user-id as an "encrypt-to-self". These keys are only used when
	      there are other recipients given either by use of --recipient or by the asked  user
	      id.   No	trust checking is performed for these user ids and even disabled keys can
	      be used.

       --hidden-encrypt-to name
	      Same as --hidden-recipient but this one is intended for use in the options file and
	      may  be  used  with  your own user-id as a hidden "encrypt-to-self". These keys are
	      only used when there are other recipients given either by use of --recipient or  by
	      the asked user id.  No trust checking is performed for these user ids and even dis-
	      abled keys can be used.

       --no-encrypt-to
	      Disable the use of all --encrypt-to and --hidden-encrypt-to keys.

       --group name=value1
	      Sets up a named group, which is similar to aliases in email programs.  Any time the
	      group  name  is  a recipient (-r or --recipient), it will be expanded to the values
	      specified. Multiple groups with the same name are automatically merged into a  sin-
	      gle group.

	      The  values  are key IDs or fingerprints, but any key description is accepted. Note
	      that a value with spaces in it will be treated as two different values.  Note  also
	      there  is  only  one level of expansion --- you cannot make an group that points to
	      another group. When used from the command line, it may be necessary  to  quote  the
	      argument	to  this  option  to prevent the shell from treating it as multiple argu-
	      ments.

       --ungroup name
	      Remove a given entry from the --group list.

       --no-groups
	      Remove all entries from the --group list.

       --local-user name

       -u     Use name as the key to sign with. Note that this option overrides --default-key.

       --try-secret-key name
	      For hidden recipients GPG needs to know the keys to use for trial decryption.   The
	      key set with --default-key is always tried first, but this is often not sufficient.
	      This option allows to set more keys to be used for trial decryption.  Although  any
	      valid user-id specification may be used for name it makes sense to use at least the
	      long keyid to avoid ambiguities.	Note that gpg-agent might pop up a pinentry for a
	      lot keys to do the trial decryption.  If you want to stop all further trial decryp-
	      tion you may use close-window button instead of the cancel button.

       --try-all-secrets
	      Don't look at the key ID as stored in the message but try all secret keys  in  turn
	      to  find	the  right  decryption	key.  This option forces the behaviour as used by
	      anonymous recipients (created by using --throw-keyids  or  --hidden-recipient)  and
	      might come handy in case where an encrypted message contains a bogus key ID.

       --skip-hidden-recipients

       --no-skip-hidden-recipients
	      During  decryption  skip	all  anonymous recipients.  This option helps in the case
	      that people use the hidden recipients feature to hide there own encrypt-to key from
	      others.  If oneself has many secret keys this may lead to a major annoyance because
	      all keys are tried in turn to decrypt soemthing which was not really  intended  for
	      it.   The drawback of this option is that it is currently not possible to decrypt a
	      message which includes real anonymous recipients.

   Input and Output

       --armor

       -a     Create ASCII armored output.  The default is to create the binary OpenPGP format.

       --no-armor
	      Assume the input data is not in ASCII armored format.

       --output file

       -o file
	      Write output to file.

       --max-output n
	      This option sets a limit on the number of bytes that will be  generated  when  pro-
	      cessing  a file. Since OpenPGP supports various levels of compression, it is possi-
	      ble that the plaintext of a given message may  be  significantly	larger	than  the
	      original	OpenPGP  message. While GnuPG works properly with such messages, there is
	      often a desire to set a maximum file size that will be generated before  processing
	      is forced to stop by the OS limits. Defaults to 0, which means "no limit".

       --import-options parameters
	      This  is	a  space or comma delimited string that gives options for importing keys.
	      Options can be prepended with a `no-' to give the  opposite  meaning.  The  options
	      are:

	      import-local-sigs
		     Allow importing key signatures marked as "local". This is not generally use-
		     ful unless a shared keyring scheme is being used.	Defaults to no.

	      repair-pks-subkey-bug
		     During import, attempt to repair the damage caused by the PKS keyserver  bug
		     (pre  version 0.9.6) that mangles keys with multiple subkeys. Note that this
		     cannot completely repair the damaged key as some crucial data is removed  by
		     the keyserver, but it does at least give you back one subkey. Defaults to no
		     for regular --import and to yes for keyserver --recv-keys.

	      merge-only
		     During import, allow key updates to existing keys, but do not allow any  new
		     keys to be imported. Defaults to no.

	      import-clean
		     After  import, compact (remove all signatures except the self-signature) any
		     user IDs from the new key that are not usable.  Then, remove any  signatures
		     from  the	new  key that are not usable.  This includes signatures that were
		     issued by keys that are not present on the keyring. This option is the  same
		     as running the --edit-key command "clean" after import. Defaults to no.

	      import-minimal
		     Import  the  smallest  key  possible. This removes all signatures except the
		     most recent self-signature on each user ID. This option is the same as  run-
		     ning the --edit-key command "minimize" after import.  Defaults to no.

       --export-options parameters
	      This  is	a  space or comma delimited string that gives options for exporting keys.
	      Options can be prepended with a `no-' to give the  opposite  meaning.  The  options
	      are:

	      export-local-sigs
		     Allow exporting key signatures marked as "local". This is not generally use-
		     ful unless a shared keyring scheme is being used.	Defaults to no.

	      export-attributes
		     Include attribute user IDs (photo IDs) while exporting. This  is  useful  to
		     export keys if they are going to be used by an OpenPGP program that does not
		     accept attribute user IDs. Defaults to yes.

	      export-sensitive-revkeys
		     Include designated revoker  information  that  was  marked  as  "sensitive".
		     Defaults to no.

	      export-reset-subkey-passwd
		     When  using  the  --export-secret-subkeys	command,  this	option resets the
		     passphrases for all exported subkeys to  empty.  This  is	useful	when  the
		     exported  subkey  is  to be used on an unattended machine where a passphrase
		     doesn't necessarily make sense. Defaults to no.

	      export-clean
		     Compact (remove all signatures from) user IDs on the key being  exported  if
		     the user IDs are not usable. Also, do not export any signatures that are not
		     usable. This includes signatures that were  issued  by  keys  that  are  not
		     present  on  the  keyring. This option is the same as running the --edit-key
		     command "clean" before export except that the local copy of the key  is  not
		     modified. Defaults to no.

	      export-minimal
		     Export  the  smallest  key  possible. This removes all signatures except the
		     most recent self-signature on each user ID. This option is the same as  run-
		     ning  the	--edit-key command "minimize" before export except that the local
		     copy of the key is not modified. Defaults to no.

       --with-colons
	      Print key listings delimited by colons. Note that the output  will  be  encoded  in
	      UTF-8 regardless of any --display-charset setting. This format is useful when GnuPG
	      is called from scripts and other programs as  it	is  easily  machine  parsed.  The
	      details  of this format are documented in the file `doc/DETAILS', which is included
	      in the GnuPG source distribution.

       --fixed-list-mode
	      Do not merge primary user ID and primary key in --with-colon listing mode and print
	      all timestamps as seconds since 1970-01-01.

       --with-fingerprint
	      Same as the command --fingerprint but changes only the format of the output and may
	      be used together with another command.

       --with-keygrip
	      Include the keygrip in the key listings.

   OpenPGP protocol specific options.

       -t, --textmode

       --no-textmode
	      Treat input files as text and store them in the OpenPGP canonical  text  form  with
	      standard	"CRLF"	line  endings.	This  also sets the necessary flags to inform the
	      recipient that the encrypted or signed data is text and may need its  line  endings
	      converted back to whatever the local system uses. This option is useful when commu-
	      nicating between two platforms that have different line ending  conventions  (UNIX-
	      like  to	Mac, Mac to Windows, etc). --no-textmode disables this option, and is the
	      default.

	      If -t (but not --textmode) is used together with armoring and signing, this enables
	      clearsigned  messages.  This  kludge  is needed for command-line compatibility with
	      command-line versions of PGP; normally you  would  use  --sign  or  --clearsign  to
	      select the type of the signature.

       --force-v3-sigs

       --no-force-v3-sigs
	      OpenPGP  states  that  an implementation should generate v4 signatures but PGP ver-
	      sions 5 through 7 only recognize v4 signatures on key material. This option  forces
	      v3  signatures for signatures on data.  Note that this option implies --no-ask-sig-
	      expire, and unsets --sig-policy-url, --sig-notation,  and  --sig-keyserver-url,  as
	      these features cannot be used with v3 signatures.  --no-force-v3-sigs disables this
	      option.  Defaults to no.

       --force-v4-certs

       --no-force-v4-certs
	      Always use v4 key signatures even on v3 keys. This option also changes the  default
	      hash  algorithm  for  v3	RSA keys from MD5 to SHA-1.  --no-force-v4-certs disables
	      this option.

       --force-mdc
	      Force the use of encryption with a modification detection code. This is always used
	      with  the newer ciphers (those with a blocksize greater than 64 bits), or if all of
	      the recipient keys indicate MDC support in their feature flags.

       --disable-mdc
	      Disable the use of the modification detection code. Note that by using this option,
	      the encrypted message becomes vulnerable to a message modification attack.

       --personal-cipher-preferences string
	      Set  the list of personal cipher preferences to string.  Use gpg --version to get a
	      list of available algorithms, and use none to  set  no  preference  at  all.   This
	      allows  the user to safely override the algorithm chosen by the recipient key pref-
	      erences, as GPG will only select an algorithm that is  usable  by  all  recipients.
	      The most highly ranked cipher in this list is also used for the --symmetric encryp-
	      tion command.

       --personal-digest-preferences string
	      Set the list of personal digest preferences to string.  Use gpg --version to get	a
	      list  of	available  algorithms,	and  use  none to set no preference at all.  This
	      allows the user to safely override the algorithm chosen by the recipient key  pref-
	      erences,	as  GPG  will  only select an algorithm that is usable by all recipients.
	      The most highly ranked digest algorithm in this list  is	also  used  when  signing
	      without encryption (e.g. --clearsign or --sign). The default value is SHA-1.

       --personal-compress-preferences string
	      Set  the	list of personal compression preferences to string.  Use gpg --version to
	      get a list of available algorithms, and use none to set no preference at all.  This
	      allows  the user to safely override the algorithm chosen by the recipient key pref-
	      erences, as GPG will only select an algorithm that is  usable  by  all  recipients.
	      The  most  highly ranked compression algorithm in this list is also used when there
	      are no recipient keys to consider (e.g. --symmetric).

       --s2k-cipher-algo name
	      Use name as the cipher algorithm used to protect secret keys.  The  default  cipher
	      is  CAST5.  This	cipher	is  also  used for conventional encryption if --personal-
	      cipher-preferences and --cipher-algo is not given.

       --s2k-digest-algo name
	      Use name as the digest algorithm used to mangle the passphrases.	The default algo-
	      rithm is SHA-1.

       --s2k-mode n
	      Selects  how  passphrases  are  mangled. If n is 0 a plain passphrase (which is not
	      recommended) will be used, a 1 adds a salt to the passphrase and a 3 (the  default)
	      iterates	the  whole process a number of times (see --s2k-count).  Unless --rfc1991
	      is used, this mode is also used for conventional encryption.

       --s2k-count n
	      Specify how many times the passphrase mangling is repeated.  This value  may  range
	      between  1024  and 65011712 inclusive, and the default is 65536.	Note that not all
	      values in the 1024-65011712 range are legal and if an illegal  value  is	selected,
	      GnuPG  will round up to the nearest legal value.	This option is only meaningful if
	      --s2k-mode is 3.

   Compliance options

       These options control what GnuPG is compliant to. Only one of these options may be  active
       at a time. Note that the default setting of this is nearly always the correct one. See the
       INTEROPERABILITY WITH OTHER OPENPGP PROGRAMS section  below  before  using  one	of  these
       options.

       --gnupg
	      Use  standard GnuPG behavior. This is essentially OpenPGP behavior (see --openpgp),
	      but with some additional workarounds for common compatibility problems in different
	      versions	of PGP. This is the default option, so it is not generally needed, but it
	      may be useful to override a different compliance option in the gpg.conf file.

       --openpgp
	      Reset all packet, cipher and digest options to strict OpenPGP  behavior.	Use  this
	      option to reset all previous options like --s2k-*, --cipher-algo, --digest-algo and
	      --compress-algo to OpenPGP compliant values. All PGP workarounds are disabled.

       --rfc4880
	      Reset all packet, cipher and digest options to strict RFC-4880 behavior. Note  that
	      this is currently the same thing as --openpgp.

       --rfc2440
	      Reset all packet, cipher and digest options to strict RFC-2440 behavior.

       --rfc1991
	      Try to be more RFC-1991 (PGP 2.x) compliant.

       --pgp2 Set up all options to be as PGP 2.x compliant as possible, and warn if an action is
	      taken (e.g. encrypting to a non-RSA key) that will create a message  that  PGP  2.x
	      will  not  be able to handle. Note that `PGP 2.x' here means `MIT PGP 2.6.2'. There
	      are other versions of PGP 2.x available, but the MIT release is a good common base-
	      line.

	      This option implies --rfc1991 --disable-mdc --no-force-v4-certs --escape-from-lines
	      --force-v3-sigs --cipher-algo IDEA --digest-algo MD5 --compress-algo ZIP.  It  also
	      disables --textmode when encrypting.

       --pgp6 Set  up all options to be as PGP 6 compliant as possible. This restricts you to the
	      ciphers IDEA (if the IDEA plugin is installed), 3DES, and CAST5,	the  hashes  MD5,
	      SHA1 and RIPEMD160, and the compression algorithms none and ZIP. This also disables
	      --throw-keyids, and making signatures with signing subkeys as PGP 6 does not under-
	      stand signatures made by signing subkeys.

	      This option implies --disable-mdc --escape-from-lines --force-v3-sigs.

       --pgp7 Set  up  all  options  to  be  as PGP 7 compliant as possible. This is identical to
	      --pgp6 except that MDCs are not disabled, and the  list  of  allowable  ciphers  is
	      expanded to add AES128, AES192, AES256, and TWOFISH.

       --pgp8 Set  up  all options to be as PGP 8 compliant as possible. PGP 8 is a lot closer to
	      the OpenPGP standard than previous versions of PGP, so all  this	does  is  disable
	      --throw-keyids  and set --escape-from-lines.  All algorithms are allowed except for
	      the SHA224, SHA384, and SHA512 digests.

   Doing things one usually doesn't want to do.

       -n

       --dry-run
	      Don't make any changes (this is not completely implemented).

       --list-only
	      Changes the behaviour of some commands. This is like  --dry-run  but  different  in
	      some  cases.  The semantic of this command may be extended in the future. Currently
	      it only skips the actual decryption pass and therefore enables a	fast  listing  of
	      the encryption keys.

       -i

       --interactive
	      Prompt before overwriting any files.

       --debug-level level
	      Select  the debug level for investigating problems. level may be a numeric value or
	      by a keyword:

	      none   No debugging at all.  A value of less than 1 may be used instead of the key-
		     word.

	      basic  Some  basic  debug messages.  A value between 1 and 2 may be used instead of
		     the keyword.

	      advanced
		     More verbose debug messages.  A value between 3 and 5 may be used instead of
		     the keyword.

	      expert Even more detailed messages.  A value between 6 and 8 may be used instead of
		     the keyword.

	      guru   All of the debug messages you can get. A value greater than 8  may  be  used
		     instead  of the keyword.  The creation of hash tracing files is only enabled
		     if the keyword is used.

       How these messages are mapped to the actual debugging  flags  is  not  specified  and  may
       change  with  newer  releases of this program. They are however carefully selected to best
       aid in debugging.

       --debug flags
	      Set debugging flags. All flags are or-ed and flags may be given in C  syntax  (e.g.
	      0x0042).

       --debug-all
	      Set all useful debugging flags.

       --debug-ccid-driver
	      Enable  debug  output from the included CCID driver for smartcards.  Note that this
	      option is only available on some system.

       --faked-system-time epoch
	      This option is only useful for testing; it sets the system time back  or	forth  to
	      epoch  which  is	the number of seconds elapsed since the year 1970.  Alternatively
	      epoch may be given as a full ISO time string (e.g. "20070924T154812").

       --enable-progress-filter
	      Enable certain PROGRESS status outputs. This option allows frontends to  display	a
	      progress indicator while gpg is processing larger files.	There is a slight perfor-
	      mance overhead using it.

       --status-fd n
	      Write special status strings to the file descriptor n.  See the file DETAILS in the
	      documentation for a listing of them.

       --status-file file
	      Same as --status-fd, except the status data is written to file file.

       --logger-fd n
	      Write log output to file descriptor n and not to STDERR.

       --log-file file

       --logger-file file
	      Same  as	--logger-fd,  except  the logger data is written to file file.	Note that
	      --log-file is only implemented for GnuPG-2.

       --attribute-fd n
	      Write attribute subpackets to the file descriptor n. This is most  useful  for  use
	      with  --status-fd, since the status messages are needed to separate out the various
	      subpackets from the stream delivered to the file descriptor.

       --attribute-file file
	      Same as --attribute-fd, except the attribute data is written to file file.

       --comment string

       --no-comments
	      Use string as a comment string in clear text signatures and ASCII armored  messages
	      or  keys (see --armor). The default behavior is not to use a comment string. --com-
	      ment may be repeated multiple times to get multiple comment strings.  --no-comments
	      removes  all  comments.	It  is a good idea to keep the length of a single comment
	      below 60 characters to avoid problems with mail programs wrapping such lines.  Note
	      that  comment  lines,  like all other header lines, are not protected by the signa-
	      ture.

       --emit-version

       --no-emit-version
	      Force inclusion of the version string in ASCII armored  output.	--no-emit-version
	      disables this option.

       --sig-notation name=value

       --cert-notation name=value

       -N, --set-notation name=value
	      Put  the	name  value  pair into the signature as notation data.	name must consist
	      only of printable characters or spaces, and must contain a  '@'  character  in  the
	      form  keyname@domain.example.com	(substituting  the appropriate keyname and domain
	      name, of course).  This is to help prevent pollution of the IETF reserved  notation
	      namespace.  The  --expert  flag overrides the '@' check. value may be any printable
	      string; it will be encoded in UTF8, so you should check that your --display-charset
	      is  set  correctly.  If  you prefix name with an exclamation mark (!), the notation
	      data will be flagged as critical (rfc2440:5.2.3.15). --sig-notation sets a notation
	      for data signatures. --cert-notation sets a notation for key signatures (certifica-
	      tions). --set-notation sets both.

	      There are special codes that may be used in notation names. "%k" will  be  expanded
	      into the key ID of the key being signed, "%K" into the long key ID of the key being
	      signed, "%f" into the fingerprint of the key being signed, "%s" into the key ID  of
	      the  key making the signature, "%S" into the long key ID of the key making the sig-
	      nature, "%g" into the fingerprint of the key making the signature (which might be a
	      subkey),	"%p" into the fingerprint of the primary key of the key making the signa-
	      ture, "%c" into the signature count from the OpenPGP smartcard, and "%%" results in
	      a  single "%". %k, %K, and %f are only meaningful when making a key signature (cer-
	      tification), and %c is only meaningful when using the OpenPGP smartcard.

       --sig-policy-url string

       --cert-policy-url string

       --set-policy-url string
	      Use string as a Policy URL for signatures (rfc2440:5.2.3.19).   If  you  prefix  it
	      with  an	exclamation  mark (!), the policy URL packet will be flagged as critical.
	      --sig-policy-url sets a policy url for data signatures.  --cert-policy-url  sets	a
	      policy url for key signatures (certifications). --set-policy-url sets both.

	      The same %-expandos used for notation data are available here as well.

       --sig-keyserver-url string
	      Use  string as a preferred keyserver URL for data signatures. If you prefix it with
	      an exclamation mark (!), the keyserver URL packet will be flagged as critical.

	      The same %-expandos used for notation data are available here as well.

       --set-filename string
	      Use string as the filename which is stored inside  messages.   This  overrides  the
	      default, which is to use the actual filename of the file being encrypted.

       --for-your-eyes-only

       --no-for-your-eyes-only
	      Set  the	`for  your eyes only' flag in the message. This causes GnuPG to refuse to
	      save the file unless the --output option is given, and PGP to use a "secure viewer"
	      with a claimed Tempest-resistant font to display the message. This option overrides
	      --set-filename.  --no-for-your-eyes-only disables this option.

       --use-embedded-filename

       --no-use-embedded-filename
	      Try to create a file with a name as embedded in the data. This can be  a	dangerous
	      option as it allows to overwrite files. Defaults to no.

       --cipher-algo name
	      Use name as cipher algorithm. Running the program with the command --version yields
	      a list of supported algorithms. If  this	is  not  used  the  cipher  algorithm  is
	      selected	from  the preferences stored with the key. In general, you do not want to
	      use this option as it allows you to  violate  the  OpenPGP  standard.   --personal-
	      cipher-preferences is the safe way to accomplish the same thing.

       --digest-algo name
	      Use  name  as  the  message  digest algorithm. Running the program with the command
	      --version yields a list of supported algorithms. In general, you do not want to use
	      this  option  as	it allows you to violate the OpenPGP standard. --personal-digest-
	      preferences is the safe way to accomplish the same thing.

       --compress-algo name
	      Use compression algorithm name. "zlib"  is  RFC-1950  ZLIB  compression.	"zip"  is
	      RFC-1951	ZIP  compression which is used by PGP.	"bzip2" is a more modern compres-
	      sion scheme that can compress some things better than zip or zlib, but at the  cost
	      of  more memory used during compression and decompression. "uncompressed" or "none"
	      disables compression. If this option is not used, the default behavior is to  exam-
	      ine  the	recipient key preferences to see which algorithms the recipient supports.
	      If all else fails, ZIP is used for maximum compatibility.

	      ZLIB may give better compression results than ZIP, as the compression  window  size
	      is not limited to 8k. BZIP2 may give even better compression results than that, but
	      will use a significantly larger amount of memory while compressing and  decompress-
	      ing. This may be significant in low memory situations. Note, however, that PGP (all
	      versions) only supports ZIP compression. Using any  algorithm  other  than  ZIP  or
	      "none"  will  make  the message unreadable with PGP. In general, you do not want to
	      use this option as it allows you to violate the OpenPGP  standard.  --personal-com-
	      press-preferences is the safe way to accomplish the same thing.

       --cert-digest-algo name
	      Use  name as the message digest algorithm used when signing a key. Running the pro-
	      gram with the command --version yields a list of	supported  algorithms.	Be  aware
	      that  if	you choose an algorithm that GnuPG supports but other OpenPGP implementa-
	      tions do not, then some users will not be able to use the key signatures you  make,
	      or quite possibly your entire key.

       --disable-cipher-algo name
	      Never  allow  the  use  of  name	as  cipher algorithm.  The given name will not be
	      checked so that a later loaded algorithm will still get disabled.

       --disable-pubkey-algo name
	      Never allow the use of name as public key algorithm.  The given name  will  not  be
	      checked so that a later loaded algorithm will still get disabled.

       --throw-keyids

       --no-throw-keyids
	      Do  not  put  the recipient key IDs into encrypted messages. This helps to hide the
	      receivers of the message and is a limited countermeasure against traffic	analysis.
	      ([Using  a  little social engineering anyone who is able to decrypt the message can
	      check whether one of the other recipients is the one he suspects.])  On the receiv-
	      ing side, it may slow down the decryption process because all available secret keys
	      must be tried.  --no-throw-keyids disables this option. This option is  essentially
	      the same as using --hidden-recipient for all recipients.

       --not-dash-escaped
	      This  option  changes the behavior of cleartext signatures so that they can be used
	      for patch files. You should not send such an armored file  via  email  because  all
	      spaces  and line endings are hashed too. You can not use this option for data which
	      has 5 dashes at the beginning of a line, patch files don't  have	this.  A  special
	      armor header line tells GnuPG about this cleartext signature option.

       --escape-from-lines

       --no-escape-from-lines
	      Because  some  mailers change lines starting with "From " to ">From " it is good to
	      handle such lines in a special way when creating cleartext  signatures  to  prevent
	      the mail system from breaking the signature. Note that all other PGP versions do it
	      this way too.  Enabled by default. --no-escape-from-lines disables this option.

       --passphrase-repeat n
	      Specify how many times gpg will request a new passphrase be repeated.  This is use-
	      ful for helping memorize a passphrase.  Defaults to 1 repetition.

       --passphrase-fd n
	      Read  the  passphrase from file descriptor n. Only the first line will be read from
	      file descriptor n. If you use 0 for n, the passphrase will be read from STDIN. This
	      can only be used if only one passphrase is supplied.

       --passphrase-file file
	      Read  the  passphrase  from  file  file. Only the first line will be read from file
	      file. This can only be used if  only  one  passphrase  is  supplied.  Obviously,	a
	      passphrase  stored  in  a  file is of questionable security if other users can read
	      this file. Don't use this option if you can avoid it.

       --passphrase string
	      Use string as the passphrase. This can only be used if only one passphrase is  sup-
	      plied.  Obviously,  this	is  of very questionable security on a multi-user system.
	      Don't use this option if you can avoid it.

       --command-fd n
	      This is a replacement for the deprecated shared-memory IPC mode.	If this option is
	      enabled,	user  input  on questions is not expected from the TTY but from the given
	      file descriptor. It  should  be  used  together  with  --status-fd.  See	the  file
	      doc/DETAILS in the source distribution for details on how to use it.

       --command-file file
	      Same as --command-fd, except the commands are read out of file file

       --allow-non-selfsigned-uid

       --no-allow-non-selfsigned-uid
	      Allow  the  import and use of keys with user IDs which are not self-signed. This is
	      not recommended, as a non self-signed user ID is trivial to forge.  --no-allow-non-
	      selfsigned-uid disables.

       --allow-freeform-uid
	      Disable  all  checks  on	the  form of the user ID while generating a new one. This
	      option should only be used in very special environments as it does not  ensure  the
	      de-facto standard format of user IDs.

       --ignore-time-conflict
	      GnuPG  normally checks that the timestamps associated with keys and signatures have
	      plausible values. However, sometimes a signature seems to be older than the key due
	      to  clock  problems.  This  option  makes  these	checks	just  a warning. See also
	      --ignore-valid-from for timestamp issues on subkeys.

       --ignore-valid-from
	      GnuPG normally does not select and use subkeys created in the future.  This  option
	      allows  the  use of such keys and thus exhibits the pre-1.0.7 behaviour. You should
	      not use this option unless you there is some clock problem. See also --ignore-time-
	      conflict for timestamp issues with signatures.

       --ignore-crc-error
	      The ASCII armor used by OpenPGP is protected by a CRC checksum against transmission
	      errors. Occasionally the CRC gets mangled somewhere on the transmission channel but
	      the  actual  content  (which  is protected by the OpenPGP protocol anyway) is still
	      okay. This option allows GnuPG to ignore CRC errors.

       --ignore-mdc-error
	      This option changes a MDC integrity protection failure into a warning.  This can be
	      useful  if  a message is partially corrupt, but it is necessary to get as much data
	      as possible out of the corrupt message.  However, be aware that  a  MDC  protection
	      failure  may  also  mean	that  the  message  was tampered with intentionally by an
	      attacker.

       --no-default-keyring
	      Do not add the default keyrings to the list of keyrings. Note that GnuPG	will  not
	      operate  without	any keyrings, so if you use this option and do not provide alter-
	      nate keyrings via --keyring or --secret-keyring, then  GnuPG  will  still  use  the
	      default public or secret keyrings.

       --skip-verify
	      Skip  the  signature  verification  step.  This  may be used to make the decryption
	      faster if the signature verification is not needed.

       --with-key-data
	      Print key listings delimited by colons (like --with-colons) and  print  the  public
	      key data.

       --fast-list-mode
	      Changes the output of the list commands to work faster; this is achieved by leaving
	      some parts empty. Some applications don't need the user ID and the  trust  informa-
	      tion  given  in  the listings. By using this options they can get a faster listing.
	      The exact behaviour of this option may change in future versions.  If you are miss-
	      ing some information, don't use this option.

       --no-literal
	      This is not for normal use. Use the source to see for what it might be useful.

       --set-filesize
	      This is not for normal use. Use the source to see for what it might be useful.

       --show-session-key
	      Display  the  session  key used for one message. See --override-session-key for the
	      counterpart of this option.

	      We think that Key Escrow is a Bad Thing; however the user should have  the  freedom
	      to  decide whether to go to prison or to reveal the content of one specific message
	      without compromising all messages ever encrypted for one secret key. DON'T  USE  IT
	      UNLESS YOU ARE REALLY FORCED TO DO SO.

       --override-session-key string
	      Don't  use  the public key but the session key string. The format of this string is
	      the same as the one printed by --show-session-key. This option is normally not used
	      but  comes  handy  in case someone forces you to reveal the content of an encrypted
	      message; using this option you can do this without handing out the secret key.

       --ask-sig-expire

       --no-ask-sig-expire
	      When making a data signature, prompt for an expiration time. If this option is  not
	      specified,  the expiration time set via --default-sig-expire is used. --no-ask-sig-
	      expire disables this option.

       --default-sig-expire
	      The default expiration time to use for signature expiration. Valid values  are  "0"
	      for  no  expiration, a number followed by the letter d (for days), w (for weeks), m
	      (for months), or y (for years) (for example "2m" for two months, or "5y"	for  five
	      years), or an absolute date in the form YYYY-MM-DD. Defaults to "0".

       --ask-cert-expire

       --no-ask-cert-expire
	      When  making  a key signature, prompt for an expiration time. If this option is not
	      specified, the expiration time set via  --default-cert-expire  is  used.	--no-ask-
	      cert-expire disables this option.

       --default-cert-expire
	      The  default expiration time to use for key signature expiration.  Valid values are
	      "0" for no expiration, a number followed by the letter d (for days), w (for weeks),
	      m (for months), or y (for years) (for example "2m" for two months, or "5y" for five
	      years), or an absolute date in the form YYYY-MM-DD. Defaults to "0".

       --allow-secret-key-import
	      This is an obsolete option and is not used anywhere.

       --allow-multiple-messages

       --no-allow-multiple-messages
	      Allow processing of multiple OpenPGP messages contained in a single file or stream.
	      Some  programs  that call GPG are not prepared to deal with multiple messages being
	      processed together, so this option defaults to no.  Note that versions of GPG prior
	      to 1.4.7 always allowed multiple messages.

	      Warning: Do not use this option unless you need it as a temporary workaround!

       --enable-special-filenames
	      This options enables a mode in which filenames of the form `-&n', where n is a non-
	      negative decimal number, refer to the file descriptor n and not to a file with that
	      name.

       --no-expensive-trust-checks
	      Experimental use only.

       --preserve-permissions
	      Don't  change the permissions of a secret keyring back to user read/write only. Use
	      this option only if you really know what you are doing.

       --default-preference-list string
	      Set the list of default preferences to string. This preference list is used for new
	      keys and becomes the default for "setpref" in the edit menu.

       --default-keyserver-url name
	      Set the default keyserver URL to name. This keyserver will be used as the keyserver
	      URL when writing a new self-signature on a key, which includes key  generation  and
	      changing preferences.

       --list-config
	      Display various internal configuration parameters of GnuPG. This option is intended
	      for external programs that call GnuPG to perform tasks, and is thus  not	generally
	      useful.  See  the  file `doc/DETAILS' in the source distribution for the details of
	      which configuration items may be listed. --list-config is only usable with  --with-
	      colons set.

       --gpgconf-list
	      This command is similar to --list-config but in general only internally used by the
	      gpgconf tool.

       --gpgconf-test
	      This is more or less dummy action.  However it parses the  configuration	file  and
	      returns  with  failure  if  the  configuration file would prevent gpg from startup.
	      Thus it may be used to run a syntax check on the configuration file.

   Deprecated options

       --load-extension name
	      Load an extension module. If name does not contain a slash it is	searched  for  in
	      the  directory  configured when GnuPG was built (generally "/usr/local/lib/gnupg").
	      Extensions are not generally useful anymore, and the use of this option  is  depre-
	      cated.

       --show-photos

       --no-show-photos
	      Causes  --list-keys, --list-sigs, --list-public-keys, --list-secret-keys, and veri-
	      fying a signature to also display the photo ID attached to the  key,  if	any.  See
	      also  --photo-viewer.  These  options are deprecated. Use --list-options [no-]show-
	      photos and/or --verify-options [no-]show-photos instead.

       --show-keyring
	      Display the keyring name at the head of key listings to show which keyring a  given
	      key  resides  on.  This  option is deprecated: use --list-options [no-]show-keyring
	      instead.

       --ctapi-driver file
	      Use file to access the smartcard reader. The current default  is	`libtowitoko.so'.
	      Note  that  the  use  of	this interface is deprecated; it may be removed in future
	      releases.

       --always-trust
	      Identical to --trust-model always. This option is deprecated.

       --show-notation

       --no-show-notation
	      Show signature notations in the --list-sigs or --check-sigs  listings  as  well  as
	      when verifying a signature with a notation in it. These options are deprecated. Use
	      --list-options  [no-]show-notation   and/or   --verify-options   [no-]show-notation
	      instead.

       --show-policy-url

       --no-show-policy-url
	      Show  policy URLs in the --list-sigs or --check-sigs listings as well as when veri-
	      fying a signature with a policy URL  in  it.  These  options  are  deprecated.  Use
	      --list-options  [no-]show-policy-url  and/or  --verify-options [no-]show-policy-url
	      instead.

EXAMPLES
       gpg -se -r Bob file
	      sign and encrypt for user Bob

       gpg --clearsign file
	      make a clear text signature

       gpg -sb file
	      make a detached signature

       gpg -u 0x12345678 -sb file
	      make a detached signature with the key 0x12345678

       gpg --list-keys user_ID
	      show keys

       gpg --fingerprint user_ID
	      show fingerprint

       gpg --verify pgpfile

       gpg --verify sigfile
	      Verify the signature of the file but do not output the data.  The  second  form  is
	      used for detached signatures, where sigfile is the detached signature (either ASCII
	      armored or binary) and are the signed data; if this is not given, the name  of  the
	      file holding the signed data is constructed by cutting off the extension (".asc" or
	      ".sig") of sigfile or by asking the user for the filename.

HOW TO SPECIFY A USER ID
       There are different ways to specify a user ID to GnuPG.	Some of them are only  valid  for
       gpg others are only good for gpgsm.  Here is the entire list of ways to specify a key:

       By key Id.
	      This  format is deduced from the length of the string and its content or 0x prefix.
	      The key Id of an X.509 certificate are the low 64 bits of  its  SHA-1  fingerprint.
	      The use of key Ids is just a shortcut, for all automated processing the fingerprint
	      should be used.

	      When using gpg an exclamation mark (!) may be appended to force using the specified
	      primary  or  secondary  key and not to try and calculate which primary or secondary
	      key to use.

	      The last four lines of the example give the key ID in their long form as internally
	      used  by the OpenPGP protocol. You can see the long key ID using the option --with-
	      colons.

	 234567C4
	 0F34E556E
	 01347A56A
	 0xAB123456

	 234AABBCC34567C4
	 0F323456784E56EAB
	 01AB3FED1347A5612
	 0x234AABBCC34567C4

       By fingerprint.
	      This format is deduced from the length of the string and its content or the 0x pre-
	      fix.  Note, that only the 20 byte version fingerprint is available with gpgsm (i.e.
	      the SHA-1 hash of the certificate).

	      When using gpg an exclamation mark (!) may be appended to force using the specified
	      primary  or  secondary  key and not to try and calculate which primary or secondary
	      key to use.

	      The best way to specify a key Id is by using  the  fingerprint.	This  avoids  any
	      ambiguities in case that there are duplicated key IDs.

	 1234343434343434C434343434343434
	 123434343434343C3434343434343734349A3434
	 0E12343434343434343434EAB3484343434343434
	 0xE12343434343434343434EAB3484343434343434

       (gpgsm also accepts colons between each pair of hexadecimal digits because this is the de-
       facto standard on how to present X.509 fingerprints.)

       By exact match on OpenPGP user ID.
	      This is denoted by a leading equal sign. It does not make sense for X.509  certifi-
	      cates.

	 =Heinrich Heine <heinrichh@uni-duesseldorf.de>

       By exact match on an email address.
	      This  is	indicated  by  enclosing the email address in the usual way with left and
	      right angles.

	 <heinrichh@uni-duesseldorf.de>

       By word match.
	      All words must match exactly (not case sensitive) but can appear in  any	order  in
	      the  user  ID  or a subjects name.  Words are any sequences of letters, digits, the
	      underscore and all characters with bit 7 set.

	 +Heinrich Heine duesseldorf

       By exact match on the subject's DN.
	      This is indicated by a leading slash, directly followed by the RFC-2253 encoded  DN
	      of  the subject.	Note that you can't use the string printed by "gpgsm --list-keys"
	      because that one as been reordered and modified for better readability; use --with-
	      colons to print the raw (but standard escaped) RFC-2253 string

	 /CN=Heinrich Heine,O=Poets,L=Paris,C=FR

       By exact match on the issuer's DN.
	      This  is	indicated  by  a leading hash mark, directly followed by a slash and then
	      directly followed by the rfc2253 encoded DN of the issuer.  This should return  the
	      Root cert of the issuer.	See note above.

	 #/CN=Root Cert,O=Poets,L=Paris,C=FR

       By exact match on serial number and issuer's DN.
	      This is indicated by a hash mark, followed by the hexadecimal representation of the
	      serial number, then followed by a slash and the RFC-2253 encoded DN of the  issuer.
	      See note above.

	 #4F03/CN=Root Cert,O=Poets,L=Paris,C=FR

       By keygrip
	      This  is	indicated  by  an  ampersand  followed by the 40 hex digits of a keygrip.
	      gpgsm prints the keygrip when using the command --dump-cert.  It does not yet  work
	      for OpenPGP keys.

	 &D75F22C3F86E355877348498CDC92BD21010A480

       By substring match.
	      This  is	the default mode but applications may want to explicitly indicate this by
	      putting the asterisk in front.  Match is not case sensitive.

	 Heine
	 *Heine

       Please note that we have reused the hash mark identifier which was used in old GnuPG  ver-
       sions  to  indicate the so called local-id.  It is not anymore used and there should be no
       conflict when used with X.509 stuff.

       Using the RFC-2253 format of DNs has the drawback that it is not possible to map them back
       to the original encoding, however we don't have to do this because our key database stores
       this encoding as meta data.

FILES
       There are a few configuration files to control certain aspects of gpg's operation.  Unless
       noted, they are expected in the current home directory (see: [option --homedir]).

       gpg.conf
	      This is the standard configuration file read by gpg on startup.  It may contain any
	      valid long option; the leading two dashes may not be entered and the option may not
	      be abbreviated.  This default name may be changed on the command line (see: [option
	      --options]).  You should backup this file.

       Note that on larger installations, it is useful to put predefined files into the directory
       `/etc/skel/.gnupg/' so that newly created users start up with a working configuration.

       For internal purposes gpg creates and maintains a few other files; They all live in in the
       current home directory (see: [option --homedir]).  Only the gpg may modify these files.

       ~/.gnupg/secring.gpg
	      The secret keyring.  You should backup this file.

       ~/.gnupg/secring.gpg.lock
	      The lock file for the secret keyring.

       ~/.gnupg/pubring.gpg
	      The public keyring.  You should backup this file.

       ~/.gnupg/pubring.gpg.lock
	      The lock file for the public keyring.

       ~/.gnupg/trustdb.gpg
	      The trust database.  There is no need to backup this file; it is better  to  backup
	      the ownertrust values (see: [option --export-ownertrust]).

       ~/.gnupg/trustdb.gpg.lock
	      The lock file for the trust database.

       ~/.gnupg/random_seed
	      A file used to preserve the state of the internal random pool.

       /usr[/local]/share/gnupg/options.skel
	      The skeleton options file.

       /usr[/local]/lib/gnupg/
	      Default location for extensions.

       Operation is further controlled by a few environment variables:

       HOME   Used to locate the default home directory.

       GNUPGHOME
	      If set directory used instead of "~/.gnupg".

       GPG_AGENT_INFO
	      Used  to	locate the gpg-agent.  This is only honored when --use-agent is set.  The
	      value consists of 3 colon delimited fields: The first  is  the  path  to	the  Unix
	      Domain  Socket,  the second the PID of the gpg-agent and the protocol version which
	      should be set to 1. When starting the gpg-agent as described in its  documentation,
	      this  variable is set to the correct value. The option --gpg-agent-info can be used
	      to override it.

       PINENTRY_USER_DATA
	      This value is passed via gpg-agent to pinentry.	It  is	useful	to  convey  extra
	      information to a custom pinentry.

       COLUMNS

       LINES  Used to size some displays to the full size of the screen.

       LANGUAGE
	      Apart  from  its use by GNU, it is used in the W32 version to override the language
	      selection done through the Registry.  If used and set to a valid and available lan-
	      guage   name   (langid),	 the   file   with   the   translation	 is  loaded  from
	      gpgdir/gnupg.nls/langid.mo.  Here gpgdir is the directory  out  of  which  the  gpg
	      binary  has  been  loaded.  If it can't be loaded the Registry is tried and as last
	      resort the native Windows locale system is used.

BUGS
       On older systems this program should be installed as setuid(root). This	is  necessary  to
       lock  memory pages. Locking memory pages prevents the operating system from writing memory
       pages (which may contain passphrases or other sensitive material) to disk. If you  get  no
       warning message about insecure memory your operating system supports locking without being
       root. The program drops root privileges as soon as locked memory is allocated.

       Note also that some systems (especially laptops) have the ability to ``suspend  to  disk''
       (also  known  as  ``safe sleep'' or ``hibernate'').  This writes all memory to disk before
       going into a low power or even powered off mode.  Unless measures are taken in the operat-
       ing  system  to	protect  the saved memory, passphrases or other sensitive material may be
       recoverable from it later.

       Before you report a bug you should first search the  mailing  list  archives  for  similar
       problems  and second check whether such a bug has already been reported to our bug tracker
       at http://bugs.gnupg.org .

SEE ALSO
       gpgv(1),

       The full documentation for this tool is maintained as a Texinfo manual.	If GnuPG and  the
       info program are properly installed at your site, the command

	 info gnupg

       should give you access to the complete manual including a menu structure and an index.

GnuPG 1.4.11				    2013-01-08					   GPG(1)


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