-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 otherwise 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
Use the simple method to determine backup file names (see the
-V method or --version-control method option), and append pref
to a file name when generating its 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
Write all files in binary mode, except for standard output and
/dev/tty. When reading, disable the heuristic for
transforming CRLF line endings into LF line endings. This
option is needed on POSIX systems when applying patches
generated on non-POSIX systems to non-POSIX files. (On POSIX
systems, file reads and writes never transform line endings.
On Windows, reads and writes do transform line endings by
default, and patches should be generated by diff --binary when
line endings are significant.)
-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 determine whether a
file should exist after patching. However, if the input is
not a context 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 questions. 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 of context 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. A fuzz factor greater
than or equal to the number of lines of context in the context
diff, ordinarily 3, ignores all context.
-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
or Perforce 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, Perforce, 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 environment
variable if it is set; if not, the default value is zero.
--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.
--merge or --merge=merge or --merge=diff3
Merge a patch file into the original files similar to diff3(1)
or merge(1). If a conflict is found, patch outputs a warning
and brackets the conflict with <<<<<<< and >>>>>>> lines. A
typical conflict will look like this:
<<<<<<<
lines from the original file
|||||||
original lines from the patch
=======
new lines from the patch
>>>>>>>
The optional argument of --merge determines the output format
for conflicts: the diff3 format shows the ||||||| section with
the original lines from the patch; in the merge format, this
section is missing. The merge format is the default.
This option implies --forward and does not take the --fuzz=num
option into account.
-n or --normal
Interpret the patch file as a normal diff.
-N or --forward
When a patch does not apply, patch usually checks if the patch
looks like it has been applied already by trying to reverse-
apply the first hunk. The --forward option prevents that.
See also -R.
-o outfile or --output=outfile
Send output to outfile instead of patching files in place. Do
not use this option if outfile is one of the files to be
patched. When outfile is -, send output to standard output,
and send any messages that would usually go to standard output
to standard error.
-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.
• Take the first existing file from the list (old, new,
index) when intuiting file names from diff headers.
• Do not remove files that are empty after patching.
• Do not ask whether to get files from RCS, ClearCase,
Perforce, or SCCS.
• Require that all options precede the files in the command
line.
• 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.
When rejectfile is -, discard rejects.
-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 information 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.)
--read-only=behavior
Behave as requested when trying to modify a read-only file:
ignore the potential problem, warn about it (the default), or
fail.
--reject-format=format
Produce reject files in the specified format (either context
or unified). Without this option, rejected hunks come out in
unified diff format if the input patch was of that format,
otherwise in ordinary context diff form.
-s or --silent or --quiet
Work silently, unless an error occurs.
--follow-symlinks
When looking for input files, follow symbolic links. Replaces
the symbolic links, instead of modifying the files the
symbolic links point to. Git-style patches to symbolic links
will no longer apply. This option exists for backwards
compatibility with previous versions of patch; its use is
discouraged.
-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 context diff headers. Unless specified
in the time stamps, assume that the context diff headers use
local time.
Use of this option with time stamps that do not include time
zones 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. Make sure
that time stamps include time zones, or generate 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 variable, 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 recognizes 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 --suffix 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 SIMPLE_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
Use the simple method to determine backup file names (see the
-V method or --version-control method option), and prefix pref
to the basename of a file name when generating its 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 the simple method to determine backup file names (see the
-V method or --version-control method option), and use suffix
as the suffix. For example, with -z - the backup file name
for src/patch/util.c is src/patch/util.c-.
-Z or --set-utc
Set the modification and access times of patched files from
time stamps given in context diff headers. Unless specified in
the time stamps, assume 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.
