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scdaemon(1) [xfree86 man page]

SCDAEMON(1)							 GNU Privacy Guard						       SCDAEMON(1)

       scdaemon - Smartcard daemon for the GnuPG system

       scdaemon [--homedir dir] [--options file] [options] --server
       scdaemon [--homedir dir] [--options file] [options] --daemon [command_line]

       The scdaemon is a daemon to manage smartcards.  It is usually invoked by gpg-agent and in general not used directly.

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

	      Print the program version and licensing information.  Not that you can abbreviate this command.

       --help, -h
	      Print a usage message summarizing the most useful command-line options.  Not that you can abbreviate this command.

	      Print a list of all available options and commands.  Not that you can abbreviate this command.

	      Run in server mode and wait for commands on the stdin.  This is default mode is to create a socket and listen for commands there.

	      Run  in  server  mode and wait for commands on the stdin as well as on an additional Unix Domain socket.	The server command GETINFO
	      may be used to get the name of that extra socket.

	      Run the program in the background.  This option is required to prevent it from being accidentally running in the background.

       --options file
	      Reads configuration from file instead of from the default per-user configuration file.  The  default  configuration  file  is  named
	      'scdaemon.conf' and expected in the '.gnupg' directory directly below the home directory of the user.

       --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 recog-
	      nized 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 HKCUSoftwareGNUGnuPG:HomeDir.


	      Outputs  additional  information while running.  You can increase the verbosity by giving several verbose commands to gpgsm, such as

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

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

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

		     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 trac-
		     ing 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.

	      All debugging options are subject to change and thus should not be used by any application program.  As the name says, they are only
	      used as helpers to debug problems.

       --debug flags
	      This  option is only useful for debugging and the behaviour may change at any time without notice.  FLAGS are bit encoded and may be
	      given in usual C-Syntax. The currently defined bits are:

	      0 (1)  command I/O

	      1 (2)  values of big number integers

	      2 (4)  low level crypto operations

	      5 (32) memory allocation

	      6 (64) caching

	      7 (128)
		     show memory statistics.

	      9 (512)
		     write hashed data to files named dbgmd-000*

	      10 (1024)
		     trace Assuan protocol.  See also option --debug-assuan-log-cats.

	      11 (2048)
		     trace APDU I/O to the card.  This may reveal sensitive data.

	      12 (4096)
		     trace some card reader related function calls.

	      Same as --debug=0xffffffff

       --debug-wait n
	      When running in server mode, wait n seconds before entering the actual processing loop and print the pid.  This gives time to attach
	      a debugger.

	      Enable  debug output from the included CCID driver for smartcards.  Using this option twice will also enable some tracing of the T=1
	      protocol.  Note that this option may reveal sensitive data.

	      This option disables all ticker functions like checking for card insertions.

	      For security reasons we won't create a core dump when the process aborts.  For debugging purposes it is sometimes  better  to  allow
	      core dump.  This options enables it and also changes the working directory to '/tmp' when running in --server mode.

	      This option appends a thread ID to the PID in the log output.

       --debug-assuan-log-cats cats
	      Changes  the  active  Libassuan  logging	categories to cats.  The value for cats is an unsigned integer given in usual C-Syntax.  A
	      value of of 0 switches to a default category.  If this option is not used the categories are taken  from	the  environment  variable
	      'ASSUAN_DEBUG'.	Note  that  this  option has only an effect if the Assuan debug flag has also been with the option --debug.  For a
	      list of categories see the Libassuan manual.

	      Don't detach the process from the console.  This is mainly useful for debugging.

       --log-file file
	      Append all logging output to file.  This is very helpful in seeing what the agent actually does.

       --pcsc-driver library
	      Use library to access the smartcard reader.  The current default is ''.  Instead of using this option you  might  also
	      want to install a symbolic link to the default file name (e.g. from '').

       --ctapi-driver library
	      Use library to access the smartcard reader.  The current default is ''.  Note that the use of this interface is depre-
	      cated; it may be removed in future releases.

	      Disable the integrated support for CCID compliant readers.  This allows to fall back to one of the other drivers even if the  inter-
	      nal 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.

	      To get a list of available CCID readers you may use this command:
	 echo scd getinfo reader_list | gpg-connect-agent --decode | awk '/^D/ {print $2}'

       --card-timeout n
	      If  n  is  not  0  and  no client is actively using the card, the card will be powered down after n seconds.  Powering down the card
	      avoids a potential risk of damaging a card when used with certain cheap readers.	This also allows non Scdaemon  aware  applications
	      to  access  the  card.   The disadvantage of using a card timeout is that accessing the card takes longer and that the user needs to
	      enter the PIN again after the next power up.

	      Note that with the current version of Scdaemon the card is powered down immediately at the next timer tick for any value of n  other
	      than 0.

	      Even if a card reader features a keypad, do not try to use it.

	      This option disables the use of admin class commands for card applications where this is supported.  Currently we support it for the
	      OpenPGP card. This commands is useful to inhibit accidental access to admin class command  which	could  ultimately  lock  the  card
	      through  wrong  PIN numbers.  Note that GnuPG versions older than 2.0.11 featured an --allow-admin command which was required to use
	      such admin commands.  This option has no more effect today because the default is now to allow admin commands.

       --disable-application name
	      This option disables the use of the card application named name.	This is mainly useful for debugging or if a application with lower
	      priority should be used by default.

	      All the long options may also be given in the configuration file after stripping off the two leading dashes.

       scdaemon supports the card applications as described below.

   The OpenPGP card application ``openpgp''

       This  application  is  currently only used by gpg but may in future also be useful with gpgsm.  Version 1 and version 2 of the card is sup-

       The specifications for these cards are available at  (  and  (

   The Telesec NetKey card ``nks''

       This  is  the main application of the Telesec cards as available in Germany.  It is a superset of the German DINSIG card.  The card is used
       by gpgsm.

   The DINSIG card application ``dinsig''

       This is an application as described in the German draft standard DIN V 66291-1.	It is intended to be used by cards supporting  the  German
       signature law and its bylaws (SigG and SigV).

   The PKCS#15 card application ``p15''

       This is common framework for smart card applications.  It is used by gpgsm.

   The Geldkarte card application ``geldkarte''

       This  is  a  simple application to display information of a German Geldkarte.  The Geldkarte is a small amount debit card application which
       comes with almost all German banking cards.

   The Undefined card application ``undefined''

       This is a stub application to allow the use of the APDU command even if no supported application is found on the card.  This application is
       not used automatically but must be explicitly requested using the SERIALNO command.

	 $ scdaemon --server -v

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

	      This is the standard configuration file read by scdaemon 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

	      If this file is present and executable, it will be called on veyer card reader's status changed. An example of this script  is  pro-
	      vided with the distribution

	      This  file  is  created by sdaemon to let other applications now about reader status changes.  Its use is now deprecated in favor of

       gpg-agent(1), gpgsm(1), gpg2(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 2.0.19							    2014-06-26							       SCDAEMON(1)
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