Unix/Linux Go Back    


RedHat 9 (Linux i386) - man page for patch (redhat section 1)

Linux & Unix Commands - Search Man Pages
Man Page or Keyword Search:   man
Select Man Page Set:       apropos Keyword Search (sections above)


PATCH(1)										 PATCH(1)

NAME
       patch - apply a diff file to an original

SYNOPSIS
       patch [options] [originalfile [patchfile]]

       but usually just

       patch -pnum <patchfile

DESCRIPTION
       patch  takes  a	patch file patchfile containing a difference listing produced by the diff
       program and applies those differences to one or more  original  files,  producing  patched
       versions.   Normally  the patched versions are put in place of the originals.  Backups can
       be made; see the -b or --backup option.	The names of the files to be patched are  usually
       taken  from the patch file, but if there's just one file to be patched it can specified on
       the command line as originalfile.

       Upon startup, patch attempts to determine the type of the diff listing,	unless	overruled
       by  a  -c  (--context), -e (--ed), -n (--normal), or -u (--unified) option.  Context diffs
       (old-style, new-style, and unified) and normal diffs are  applied  by  the  patch  program
       itself, while ed diffs are simply fed to the ed(1) editor via a pipe.

       patch  tries  to  skip  any  leading  garbage,  apply the diff, and then skip any trailing
       garbage.  Thus you could feed an article or message containing a diff  listing  to  patch,
       and  it	should work.  If the entire diff is indented by a consistent amount, or if a con-
       text diff contains lines ending in CRLF or is encapsulated one or more times by prepending
       "-  "  to  lines  starting  with  "-" as specified by Internet RFC 934, this is taken into
       account.

       With context diffs, and to a lesser extent with normal diffs, patch can	detect	when  the
       line  numbers mentioned in the patch are incorrect, and attempts to find the correct place
       to apply each hunk of the patch.  As a first guess, it takes the line number mentioned for
       the hunk, plus or minus any offset used in applying the previous hunk.  If that is not the
       correct place, patch scans both forwards and backwards for a set  of  lines  matching  the
       context	given  in the hunk.  First patch looks for a place where all lines of the context
       match.  If no such place is found, and it's a context diff, and the maximum fuzz factor is
       set  to	1 or more, then another scan takes place ignoring the first and last line of con-
       text.  If that fails, and the maximum fuzz factor is set to 2 or more, the first  two  and
       last  two  lines  of  context are ignored, and another scan is made.  (The default maximum
       fuzz factor is 2.)  If patch cannot find a place to install that hunk  of  the  patch,  it
       puts  the  hunk out to a reject file, which normally is the name of the output file plus a
       .rej suffix, or # if .rej would generate a file name that is too long (if  even	appending
       the  single character # makes the file name too long, then # replaces the file name's last
       character).  (The rejected hunk comes out in ordinary context diff form regardless of  the
       input  patch's  form.   If  the	input  was a normal diff, many of the contexts are simply
       null.)  The line numbers on the hunks in the reject file may  be  different  than  in  the
       patch  file: they reflect the approximate location patch thinks the failed hunks belong in
       the new file rather than the old one.

       As each hunk is completed, you are told if the hunk failed, and if so which line  (in  the
       new  file)  patch  thought the hunk should go on.  If the hunk is installed at a different
       line from the line number specified in the diff you are told the offset.  A  single  large
       offset  may indicate that a hunk was installed in the wrong place.  You are also told if a
       fuzz factor was used to make the match, in which case you should also be  slightly  suspi-
       cious.	If  the  --verbose  option  is	given,	you  are also told about hunks that match
       exactly.

       If no original file origfile is specified on the command line, patch tries to  figure  out
       from the leading garbage what the name of the file to edit is, using the following rules.

       First, patch takes an ordered list of candidate file names as follows:

	o If  the header is that of a context diff, patch takes the old and new file names in the
	  header.  A name is ignored if it does not have enough slashes to satisfy the	-pnum  or
	  --strip=num option.  The name /dev/null is also ignored.

	o If  there  is an Index: line in the leading garbage and if either the old and new names
	  are both absent or if patch is conforming to POSIX, patch takes the name in the  Index:
	  line.

	o For  the  purpose of the following rules, the candidate file names are considered to be
	  in the order (old, new, index), regardless of the order that they appear in the header.

       Then patch selects a file name from the candidate list as follows:

	o If some of the named files exist, patch selects the first name if conforming to  POSIX,
	  and the best name otherwise.

	o If patch is not ignoring RCS, ClearCase, and SCCS (see the -g num or --get=num option),
	  and no named files exist but an RCS, ClearCase, or SCCS master is found, patch  selects
	  the first named file with an RCS, ClearCase, or SCCS master.

	o If  no  named  files exist, no RCS, ClearCase, or SCCS master was found, some names are
	  given, patch is not conforming to POSIX, and the patch appears to create a file,  patch
	  selects the best name requiring the creation of the fewest directories.

	o If  no  file	name results from the above heuristics, you are asked for the name of the
	  file to patch, and patch selects that name.

       To determine the best of a nonempty list of file names, patch first takes  all  the  names
       with  the  fewest  path	name  components;  of those, it then takes all the names with the
       shortest basename; of those, it then takes all the shortest names; finally, it  takes  the
       first remaining name.

       Additionally,  if  the leading garbage contains a Prereq: line, patch takes the first word
       from the prerequisites line (normally a version number) and checks the  original  file  to
       see if that word can be found.  If not, patch asks for confirmation before proceeding.

       The upshot of all this is that you should be able to say, while in a news interface, some-
       thing like the following:

	  | patch -d /usr/src/local/blurfl

       and patch a file in the blurfl directory directly from the article containing the patch.

       If the patch file contains more than one patch, patch tries to apply each of  them  as  if
       they  came  from separate patch files.  This means, among other things, that it is assumed
       that the name of the file to patch must be determined for each diff listing, and that  the
       garbage	before each diff listing contains interesting things such as file names and revi-
       sion level, as mentioned previously.

OPTIONS
       -b  or  --backup
	  Make backup files.  That is, when patching a file, rename or copy the original  instead
	  of  removing	it.   When  backing  up  a file that does not exist, an empty, unreadable
	  backup file is created as a placeholder to represent the nonexistent file.  See the  -V
	  or --version-control option for details about how backup file names are determined.

       --backup-if-mismatch
	  Back up a file if the patch does not match the file exactly and if backups are not oth-
	  erwise requested.  This is the default unless patch is conforming to POSIX.

       --no-backup-if-mismatch
	  Do not back up a file if the patch does not match the file exactly and if  backups  are
	  not otherwise requested.  This is the default if patch is conforming to POSIX.

       -B pref	or  --prefix=pref
	  Prefix  pref	to a file name when generating its simple backup file name.  For example,
	  with	 -B /junk/   the   simple   backup   file   name    for    src/patch/util.c    is
	  /junk/src/patch/util.c.

       --binary
	  Read and write all files in binary mode, except for standard output and /dev/tty.  This
	  option has no effect on POSIX-conforming systems.   On  systems  like  DOS  where  this
	  option makes a difference, the patch should be generated by diff -a --binary.

       -c  or  --context
	  Interpret the patch file as a ordinary context diff.

       -d dir  or  --directory=dir
	  Change to the directory dir immediately, before doing anything else.

       -D define  or  --ifdef=define
	  Use the #ifdef ... #endif construct to mark changes, with define as the differentiating
	  symbol.

       --dry-run
	  Print the results of applying the patches without actually changing any files.

       -e  or  --ed
	  Interpret the patch file as an ed script.

       -E  or  --remove-empty-files
	  Remove output files that are empty after the patches have been applied.  Normally  this
	  option  is unnecessary, since patch can examine the time stamps on the header to deter-
	  mine whether a file should exist after patching.  However, if the input is not  a  con-
	  text diff or if patch is conforming to POSIX, patch does not remove empty patched files
	  unless this option is given.	When patch removes a file, it also attempts to remove any
	  empty ancestor directories.

       -f  or  --force
	  Assume  that	the  user knows exactly what he or she is doing, and do not ask any ques-
	  tions.  Skip patches whose headers do not say which file is to be patched; patch  files
	  even	though	they have the wrong version for the Prereq: line in the patch; and assume
	  that patches are not reversed even if they look like they are.  This	option	does  not
	  suppress commentary; use -s for that.

       -F num  or  --fuzz=num
	  Set  the maximum fuzz factor.  This option only applies to diffs that have context, and
	  causes patch to ignore up to that many lines in looking for places to install  a  hunk.
	  Note	that a larger fuzz factor increases the odds of a faulty patch.  The default fuzz
	  factor is 2, and it may not be set to more than the number of lines of context  in  the
	  context diff, ordinarily 3.

       -g num  or  --get=num
	  This option controls patch's actions when a file is under RCS or SCCS control, and does
	  not exist or is read-only and matches the default version, or  when  a  file	is  under
	  ClearCase  control  and does not exist.  If num is positive, patch gets (or checks out)
	  the file from the revision control system; if zero, patch ignores RCS,  ClearCase,  and
	  SCCS and does not get the file; and if negative, patch asks the user whether to get the
	  file.  The default value of this option is given by the value of the PATCH_GET environ-
	  ment variable if it is set; if not, the default value is zero if patch is conforming to
	  POSIX, negative otherwise.

       --help
	  Print a summary of options and exit.

       -i patchfile  or  --input=patchfile
	  Read the patch from patchfile.  If patchfile	is  -,	read  from  standard  input,  the
	  default.

       -l  or  --ignore-whitespace
	  Match  patterns  loosely,  in  case tabs or spaces have been munged in your files.  Any
	  sequence of one or more blanks in the patch file matches any sequence in  the  original
	  file, and sequences of blanks at the ends of lines are ignored.  Normal characters must
	  still match exactly.	Each line of the context must still match a line in the  original
	  file.

       -n  or  --normal
	  Interpret the patch file as a normal diff.

       -N  or  --forward
	  Ignore patches that seem to be reversed or already applied.  See also -R.

       -o outfile  or  --output=outfile
	  Send output to outfile instead of patching files in place.

       -pnum  or  --strip=num
	  Strip  the  smallest prefix containing num leading slashes from each file name found in
	  the patch file.  A sequence of one or more adjacent slashes  is  counted  as	a  single
	  slash.   This  controls how file names found in the patch file are treated, in case you
	  keep your files in a different directory than the person who sent out the  patch.   For
	  example, supposing the file name in the patch file was

	     /u/howard/src/blurfl/blurfl.c

	  setting -p0 gives the entire file name unmodified, -p1 gives

	     u/howard/src/blurfl/blurfl.c

	  without the leading slash, -p4 gives

	     blurfl/blurfl.c

	  and  not  specifying	-p  at	all just gives you blurfl.c.  Whatever you end up with is
	  looked for either in the current directory,  or  the	directory  specified  by  the  -d
	  option.

       --posix
	  Conform more strictly to the POSIX standard, as follows.

	   o Take  the	first  existing  file from the list (old, new, index) when intuiting file
	     names from diff headers.

	   o Do not remove files that are empty after patching.

	   o Do not ask whether to get files from RCS, ClearCase, or SCCS.

	   o Require that all options precede the files in the command line.

	   o Do not backup files when there is a mismatch.

       --quoting-style=word
	  Use style word to quote output names.  The word should be one of the following:

	  literal
		 Output names as-is.

	  shell  Quote names for the shell if they contain shell metacharacters  or  would  cause
		 ambiguous output.

	  shell-always
		 Quote names for the shell, even if they would normally not require quoting.

	  c	 Quote names as for a C language string.

	  escape Quote as with c except omit the surrounding double-quote characters.

	  You  can  specify  the default value of the --quoting-style option with the environment
	  variable QUOTING_STYLE.  If that environment variable is not set, the default value  is
	  shell.

       -r rejectfile  or  --reject-file=rejectfile
	  Put rejects into rejectfile instead of the default .rej file.

       -R  or  --reverse
	  Assume  that	this  patch  was  created  with the old and new files swapped.	(Yes, I'm
	  afraid that does happen occasionally, human nature being what it is.)   patch  attempts
	  to  swap  each hunk around before applying it.  Rejects come out in the swapped format.
	  The -R option does not work with ed diff scripts because there is too  little  informa-
	  tion to reconstruct the reverse operation.

	  If the first hunk of a patch fails, patch reverses the hunk to see if it can be applied
	  that way.  If it can, you are asked if you want to have  the	-R  option  set.   If  it
	  can't,  the patch continues to be applied normally.  (Note: this method cannot detect a
	  reversed patch if it is a normal diff and if the first command is an	append	(i.e.  it
	  should  have	been  a delete) since appends always succeed, due to the fact that a null
	  context matches anywhere.  Luckily, most patches add or change lines rather than delete
	  them,  so  most  reversed normal diffs begin with a delete, which fails, triggering the
	  heuristic.)

       -s  or  --silent  or  --quiet
	  Work silently, unless an error occurs.

       -t  or  --batch
	  Suppress questions like -f, but make some different  assumptions:  skip  patches  whose
	  headers do not contain file names (the same as -f); skip patches for which the file has
	  the wrong version for the Prereq: line in  the  patch;  and  assume  that  patches  are
	  reversed if they look like they are.

       -T  or  --set-time
	  Set  the  modification and access times of patched files from time stamps given in con-
	  text diff headers, assuming that the context diff headers use local time.  This  option
	  is not recommended, because patches using local time cannot easily be used by people in
	  other time zones, and because local time stamps are ambiguous when  local  clocks  move
	  backwards  during daylight-saving time adjustments.  Instead of using this option, gen-
	  erate patches with UTC and use the -Z or --set-utc option instead.

       -u  or  --unified
	  Interpret the patch file as a unified context diff.

       -v  or  --version
	  Print out patch's revision header and patch level, and exit.

       -V method  or  --version-control=method
	  Use method to determine backup file names.   The  method  can  also  be  given  by  the
	  PATCH_VERSION_CONTROL  (or,  if  that's not set, the VERSION_CONTROL) environment vari-
	  able, which is overridden by this option.  The method does not  affect  whether  backup
	  files are made; it affects only the names of any backup files that are made.

	  The value of method is like the GNU Emacs `version-control' variable; patch also recog-
	  nizes synonyms that are more descriptive.  The valid	values	for  method  are  (unique
	  abbreviations are accepted):

	  existing  or	nil
	     Make  numbered  backups  of  files that already have them, otherwise simple backups.
	     This is the default.

	  numbered  or	t
	     Make numbered backups.  The numbered backup file name for F is F.~N~ where N is  the
	     version number.

	  simple  or  never
	     Make  simple backups.  The -B or --prefix, -Y or --basename-prefix, and -z or --suf-
	     fix options specify the simple backup file name.	If  none  of  these  options  are
	     given,  then  a  simple  backup  suffix  is  used;  it  is  the  value  of  the SIM-
	     PLE_BACKUP_SUFFIX environment variable if set, and is .orig otherwise.

	  With numbered or simple backups, if the backup file name is too long, the backup suffix
	  ~  is  used  instead; if even appending ~ would make the name too long, then ~ replaces
	  the last character of the file name.

       --verbose
	  Output extra information about the work being done.

       -x num  or  --debug=num
	  Set internal debugging flags of interest only to patch patchers.

       -Y pref	or  --basename-prefix=pref
	  Prefix pref to the basename of a file name when generating its simple backup file name.
	  For  example,  with  -Y .del/  the  simple  backup  file  name  for src/patch/util.c is
	  src/patch/.del/util.c.

       -z suffix  or  --suffix=suffix
	  Use suffix as the simple backup suffix.  For example, with -z - the simple backup  file
	  name	for  src/patch/util.c is src/patch/util.c-.  The backup suffix may also be speci-
	  fied by the SIMPLE_BACKUP_SUFFIX environment variable,  which  is  overridden  by  this
	  option.

       -Z  or  --set-utc
	  Set  the  modification and access times of patched files from time stamps given in con-
	  text diff headers, assuming that the context diff  headers  use  Coordinated	Universal
	  Time (UTC, often known as GMT).  Also see the -T or --set-time option.

	  The -Z or --set-utc and -T or --set-time options normally refrain from setting a file's
	  time if the file's original time does not match the time given in the patch header,  or
	  if  its  contents do not match the patch exactly.  However, if the -f or --force option
	  is given, the file time is set regardless.

	  Due to the limitations of diff output format, these options cannot update the times  of
	  files  whose	contents  have	not  changed.  Also, if you use these options, you should
	  remove (e.g. with make clean) all files that depend on the patched files, so that later
	  invocations of make do not get confused by the patched files' times.

ENVIRONMENT
       PATCH_GET
	  This	specifies  whether  patch gets missing or read-only files from RCS, ClearCase, or
	  SCCS by default; see the -g or --get option.

       POSIXLY_CORRECT
	  If set, patch conforms more strictly to the POSIX standard by default: see the  --posix
	  option.

       QUOTING_STYLE
	  Default value of the --quoting-style option.

       SIMPLE_BACKUP_SUFFIX
	  Extension to use for simple backup file names instead of .orig.

       TMPDIR, TMP, TEMP
	  Directory  to put temporary files in; patch uses the first environment variable in this
	  list that is set.  If none are set, the default is  system-dependent;  it  is  normally
	  /tmp on Unix hosts.

       VERSION_CONTROL or PATCH_VERSION_CONTROL
	  Selects version control style; see the -v or --version-control option.

FILES
       $TMPDIR/p*
	  temporary files

       /dev/tty
	  controlling terminal; used to get answers to questions asked of the user

SEE ALSO
       diff(1), ed(1)

       Marshall  T.  Rose  and	Einar  A. Stefferud, Proposed Standard for Message Encapsulation,
       Internet RFC 934 <URL:ftp://ftp.isi.edu/in-notes/rfc934.txt> (1985-01).

NOTES FOR PATCH SENDERS
       There are several things you should bear in mind if  you  are  going  to  be  sending  out
       patches.

       Create  your  patch systematically.  A good method is the command diff -Naur old new where
       old and new identify the old and new directories.  The names old and new should	not  con-
       tain  any  slashes.   The  diff command's headers should have dates and times in Universal
       Time using traditional Unix format, so that patch recipients can use the -Z  or	--set-utc
       option.	Here is an example command, using Bourne shell syntax:

	  LC_ALL=C TZ=UTC0 diff -Naur gcc-2.7 gcc-2.8

       Tell  your recipients how to apply the patch by telling them which directory to cd to, and
       which patch options to use.  The option string -Np1 is recommended.  Test  your	procedure
       by pretending to be a recipient and applying your patch to a copy of the original files.

       You  can  save  people  a  lot of grief by keeping a patchlevel.h file which is patched to
       increment the patch level as the first diff in the patch file you send out.  If you put	a
       Prereq:	line in with the patch, it won't let them apply patches out of order without some
       warning.

       You can create a file by sending out a diff that compares /dev/null or an empty file dated
       the  Epoch  (1970-01-01	00:00:00 UTC) to the file you want to create.  This only works if
       the file you want to create doesn't exist already in the  target  directory.   Conversely,
       you  can  remove a file by sending out a context diff that compares the file to be deleted
       with an empty file dated the Epoch.  The file will be removed unless patch  is  conforming
       to  POSIX and the -E or --remove-empty-files option is not given.  An easy way to generate
       patches that create and remove files is to use GNU diff's -N or --new-file option.

       If the recipient is supposed to use the -pN option, do not send	output	that  looks  like
       this:

	  diff -Naur v2.0.29/prog/README prog/README
	  --- v2.0.29/prog/README   Mon Mar 10 15:13:12 1997
	  +++ prog/README   Mon Mar 17 14:58:22 1997

       because	the  two  file names have different numbers of slashes, and different versions of
       patch interpret the file names differently.  To avoid confusion, send  output  that  looks
       like this instead:

	  diff -Naur v2.0.29/prog/README v2.0.30/prog/README
	  --- v2.0.29/prog/README   Mon Mar 10 15:13:12 1997
	  +++ v2.0.30/prog/README   Mon Mar 17 14:58:22 1997

       Avoid  sending  patches	that compare backup file names like README.orig, since this might
       confuse patch into patching a backup file instead of the real file.  Instead, send patches
       that  compare  the  same  base  file  names  in different directories, e.g. old/README and
       new/README.

       Take care not to send out reversed patches, since it  makes  people  wonder  whether  they
       already applied the patch.

       Try  not to have your patch modify derived files (e.g. the file configure where there is a
       line configure: configure.in in your makefile), since the  recipient  should  be  able  to
       regenerate  the	derived  files anyway.	If you must send diffs of derived files, generate
       the diffs using UTC, have the recipients apply the patch with the -Z or --set-utc  option,
       and  have  them	remove	any  unpatched	files  that  depend  on  patched files (e.g. with
       make clean).

       While you may be able to get away with putting 582 diff listings into one file, it may  be
       wiser to group related patches into separate files in case something goes haywire.

DIAGNOSTICS
       Diagnostics generally indicate that patch couldn't parse your patch file.

       If  the	--verbose option is given, the message Hmm... indicates that there is unprocessed
       text in the patch file and that patch is attempting to intuit whether there is a patch  in
       that text and, if so, what kind of patch it is.

       patch's	exit status is 0 if all hunks are applied successfully, 1 if some hunks cannot be
       applied, and 2 if there is more serious trouble.  When applying a set of patches in a loop
       it  behooves you to check this exit status so you don't apply a later patch to a partially
       patched file.

CAVEATS
       Context diffs cannot reliably represent the creation or deletion  of  empty  files,  empty
       directories,  or  special files such as symbolic links.	Nor can they represent changes to
       file metadata like ownership, permissions, or whether one file is a hard link to  another.
       If  changes  like  these are also required, separate instructions (e.g. a shell script) to
       accomplish them should accompany the patch.

       patch cannot tell if the line numbers are off in an ed script, and  can	detect	bad  line
       numbers	in  a  normal diff only when it finds a change or deletion.  A context diff using
       fuzz factor 3 may have the same problem.  Until a suitable interactive interface is added,
       you should probably do a context diff in these cases to see if the changes made sense.  Of
       course, compiling without errors is a pretty good indication that the  patch  worked,  but
       not always.

       patch  usually  produces  the  correct  results, even when it has to do a lot of guessing.
       However, the results are guaranteed to be correct  only	when  the  patch  is  applied  to
       exactly the same version of the file that the patch was generated from.

COMPATIBILITY ISSUES
       The POSIX standard specifies behavior that differs from patch's traditional behavior.  You
       should be aware of these differences if you must interoperate with patch versions 2.1  and
       earlier, which do not conform to POSIX.

	o In  traditional  patch, the -p option's operand was optional, and a bare -p was equiva-
	  lent to -p0.	The -p option now requires an operand, and -p 0 is now equivalent to -p0.
	  For maximum compatibility, use options like -p0 and -p1.

	  Also,  traditional patch simply counted slashes when stripping path prefixes; patch now
	  counts pathname components.  That is, a sequence of one or more  adjacent  slashes  now
	  counts as a single slash.  For maximum portability, avoid sending patches containing //
	  in file names.

	o In traditional patch, backups were enabled by default.  This behavior  is  now  enabled
	  with the -b or --backup option.

	  Conversely,  in POSIX patch, backups are never made, even when there is a mismatch.  In
	  GNU patch, this behavior is enabled with the --no-backup-if-mismatch option, or by con-
	  forming  to POSIX with the --posix option or by setting the POSIXLY_CORRECT environment
	  variable.

	  The -b suffix option of traditional patch is equivalent to the -b -z suffix options  of
	  GNU patch.

	o Traditional patch used a complicated (and incompletely documented) method to intuit the
	  name of the file to be patched from the patch header.  This method did not  conform  to
	  POSIX,  and  had  a  few gotchas.  Now patch uses a different, equally complicated (but
	  better documented) method that is optionally POSIX-conforming; we  hope  it  has  fewer
	  gotchas.   The  two methods are compatible if the file names in the context diff header
	  and the Index: line are all identical after prefix-stripping.  Your patch  is  normally
	  compatible if each header's file names all contain the same number of slashes.

	o When	traditional  patch  asked  the	user a question, it sent the question to standard
	  error and looked for an answer from the first file in the following  list  that  was	a
	  terminal:  standard  error,  standard  output, /dev/tty, and standard input.	Now patch
	  sends questions to standard output and gets answers from /dev/tty.  Defaults	for  some
	  answers  have  been  changed	so that patch never goes into an infinite loop when using
	  default answers.

	o Traditional patch exited with a status value that counted the number of bad  hunks,  or
	  with	status	1 if there was real trouble.  Now patch exits with status 1 if some hunks
	  failed, or with 2 if there was real trouble.

	o Limit yourself to the following options when sending instructions meant to be  executed
	  by  anyone  running  GNU  patch,  traditional patch, or a patch that conforms to POSIX.
	  Spaces are significant in the following list, and operands are required.

	     -c
	     -d dir
	     -D define
	     -e
	     -l
	     -n
	     -N
	     -o outfile
	     -pnum
	     -R
	     -r rejectfile

BUGS
       Please report bugs via email to <bug-gnu-utils@gnu.org>.

       patch could be smarter about partial matches,  excessively  deviant  offsets  and  swapped
       code, but that would take an extra pass.

       If code has been duplicated (for instance with #ifdef OLDCODE ... #else ... #endif), patch
       is incapable of patching both versions, and, if it works at all,  will  likely  patch  the
       wrong one, and tell you that it succeeded to boot.

       If  you	apply  a  patch  you've already applied, patch thinks it is a reversed patch, and
       offers to un-apply the patch.  This could be construed as a feature.

COPYING
       Copyright 1984, 1985, 1986, 1988 Larry Wall.
       Copyright 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998 Free Software Founda-
       tion, Inc.

       Permission  is  granted to make and distribute verbatim copies of this manual provided the
       copyright notice and this permission notice are preserved on all copies.

       Permission is granted to copy and distribute modified versions of this  manual  under  the
       conditions  for	verbatim copying, provided that the entire resulting derived work is dis-
       tributed under the terms of a permission notice identical to this one.

       Permission is granted to copy and distribute translations of this manual into another lan-
       guage,  under  the  above  conditions  for  modified versions, except that this permission
       notice may be included in translations approved by the copyright holders instead of in the
       original English.

AUTHORS
       Larry  Wall  wrote  the	original version of patch.  Paul Eggert removed patch's arbitrary
       limits; added support for binary files, setting file times, and deleting files;	and  made
       it  conform  better to POSIX.  Other contributors include Wayne Davison, who added unidiff
       support, and David MacKenzie, who added configuration and backup support.

GNU					    1998/03/21					 PATCH(1)
Unix & Linux Commands & Man Pages : ©2000 - 2018 Unix and Linux Forums


All times are GMT -4. The time now is 10:52 PM.