DESCRIPTION
ppaattcchh takes a patch file patchfile containing a difference listing pro-
duced by the ddiiffff program and applies those differences to one or more
original files, producing patched versions. Normally the patched ver-
sions are put in place of the originals. Backups can be made; see the
-bb or --bbaacckkuupp option. The names of the files to be patched are usu-
ally 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 -cc (--ccoonntteexxtt), -ee (--eedd), -nn (--nnoorrmmaall), or -uu
(--uunniiffiieedd) option. Context diffs (old-style, new-style, and unified)
and normal diffs are applied by the ppaattcchh program itself, while eedd
diffs are simply fed to the eedd(1) editor via a pipe.
ppaattcchh tries to skip any leading garbage, apply the diff, and then skip
any trailing garbage. Thus you could feed an article or message con-
taining a diff listing to ppaattcchh, and it should work. If the entire
diff is indented by a consistent amount, or if a context 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. After removing indenting or encapsulation,
lines beginning with ## are ignored, as they are considered to be com-
ments.
With context diffs, and to a lesser extent with normal diffs, ppaattcchh 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, ppaattcchh scans both forwards and backwards for a set of
lines matching the context given in the hunk. First ppaattcchh 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
context. 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
ppaattcchh 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 ..rreejj suffix, or ## if ..rreejj 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 con-
texts are simply null.) The line numbers on the hunks in the reject
file may be different than in the patch file: they reflect the approxi-
mate 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) ppaattcchh thought the hunk should go on. If
the hunk is installed at a different line from the line number speci-
fied 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 suspicious. If the --vveerrbboossee option is given,
you are also told about hunks that match exactly.
If no original file origfile is specified on the command line, ppaattcchh
tries to figure out from the leading garbage what the name of the file
to edit is, using the following rules.
First, ppaattcchh takes an ordered list of candidate file names as follows:
++oo If the header is that of a context diff, ppaattcchh takes the old and new
file names in the header. A name is ignored if it does not have
enough slashes to satisfy the -ppnum or --ssttrriipp==num option. The name
//ddeevv//nnuullll is also ignored.
++oo If there is an IInnddeexx:: line in the leading garbage and if either the
old and new names are both absent or if ppaattcchh is conforming to
POSIX, ppaattcchh takes the name in the IInnddeexx:: line.
++oo 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 ppaattcchh selects a file name from the candidate list as follows:
++oo If some of the named files exist, ppaattcchh selects the first name if
conforming to POSIX, and the best name otherwise.
++oo If ppaattcchh is not ignoring RCS, ClearCase, Perforce, and SCCS (see the
-gg num or --ggeett==num option), and no named files exist but an RCS,
ClearCase, Perforce, or SCCS master is found, ppaattcchh selects the
first named file with an RCS, ClearCase, Perforce, or SCCS master.
++oo If no named files exist, no RCS, ClearCase, Perforce, or SCCS master
was found, some names are given, ppaattcchh is not conforming to POSIX,
and the patch appears to create a file, ppaattcchh selects the best name
requiring the creation of the fewest directories.
++oo If no file name results from the above heuristics, you are asked for
the name of the file to patch, and ppaattcchh selects that name.
To determine the best of a nonempty list of file names, ppaattcchh 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 PPrreerreeqq:: line, ppaattcchh
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, ppaattcchh asks for confirmation before proceeding.
The upshot of all this is that you should be able to say, while in a
news interface, something like the following:
|| ppaattcchh -dd //uussrr//ssrrcc//llooccaall//bblluurrffll
and patch a file in the bblluurrffll directory directly from the article con-
taining the patch.
If the patch file contains more than one patch, ppaattcchh 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 revision level, as mentioned previously.
OOPPTTIIOONNSS
-bb or --bbaacckkuupp
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 -VV or --vveerr-
ssiioonn-ccoonnttrrooll option for details about how backup file names are
determined.
--bbaacckkuupp-iiff-mmiissmmaattcchh
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
ppaattcchh is conforming to POSIX.
--nnoo-bbaacckkuupp-iiff-mmiissmmaattcchh
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
ppaattcchh is conforming to POSIX.
-BB pref or --pprreeffiixx==pref
Prefix pref to a file name when generating its simple backup file
name. For example, with -BB //jjuunnkk// the simple backup file name for
ssrrcc//ppaattcchh//uuttiill..cc is //jjuunnkk//ssrrcc//ppaattcchh//uuttiill..cc.
--bbiinnaarryy
Read and write all files in binary mode, except for standard output
and //ddeevv//ttttyy. This option has no effect on POSIX-conforming sys-
tems. On systems like DOS where this option makes a difference, the
patch should be generated by ddiiffff -aa --bbiinnaarryy.
-cc or --ccoonntteexxtt
Interpret the patch file as a ordinary context diff.
-dd dir or --ddiirreeccttoorryy==dir
Change to the directory dir immediately, before doing anything else.
-DD define or --iiffddeeff==define
Use the ##iiffddeeff ... ##eennddiiff construct to mark changes, with define as
the differentiating symbol.
--ddrryy-rruunn
Print the results of applying the patches without actually changing
any files.
-ee or --eedd
Interpret the patch file as an eedd script.
-EE or --rreemmoovvee-eemmppttyy-ffiilleess
Remove output files that are empty after the patches have been
applied. Normally this option is unnecessary, since ppaattcchh can exam-
ine 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 ppaattcchh is conforming to POSIX, ppaattcchh does not remove empty
patched files unless this option is given. When ppaattcchh removes a
file, it also attempts to remove any empty ancestor directories.
-ff or --ffoorrccee
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 PPrreerreeqq:: 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 -ss for that.
-FF num or --ffuuzzzz==num
Set the maximum fuzz factor. This option only applies to diffs that
have context, and causes ppaattcchh to ignore up to that many lines in
looking for places to install a hunk. Note that a larger fuzz fac-
tor 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 con-
text in the context diff, ordinarily 3.
-gg num or --ggeett==num
This option controls ppaattcchh'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 con-
trol and does not exist. If num is positive, ppaattcchh gets (or checks
out) the file from the revision control system; if zero, ppaattcchh
ignores RCS, ClearCase, Perforce, and SCCS and does not get the
file; and if negative, ppaattcchh asks the user whether to get the file.
The default value of this option is given by the value of the
PPAATTCCHHGGEETT environment variable if it is set; if not, the default
value is zero if ppaattcchh is conforming to POSIX, negative otherwise.
--hheellpp
Print a summary of options and exit.
-ii patchfile or --iinnppuutt==patchfile
Read the patch from patchfile. If patchfile is -, read from stan-
dard input, the default.
-ll or --iiggnnoorree-wwhhiitteessppaaccee
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.
-nn or --nnoorrmmaall
Interpret the patch file as a normal diff.
-NN or --ffoorrwwaarrdd
Ignore patches that seem to be reversed or already applied. See
also -RR.
-oo outfile or --oouuttppuutt==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.
-ppnum or --ssttrriipp==num
Strip the smallest prefix containing num leading slashes from each
file name found in the patch file. A sequence of one or more adja-
cent 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
//uu//hhoowwaarrdd//ssrrcc//bblluurrffll//bblluurrffll..cc
setting -pp00 gives the entire file name unmodified, -pp11 gives
uu//hhoowwaarrdd//ssrrcc//bblluurrffll//bblluurrffll..cc
without the leading slash, -pp44 gives
bblluurrffll//bblluurrffll..cc
and not specifying -pp at all just gives you bblluurrffll..cc. Whatever you
end up with is looked for either in the current directory, or the
directory specified by the -dd option.
--ppoossiixx
Conform more strictly to the POSIX standard, as follows.
++oo Take the first existing file from the list (old, new, index) when
intuiting file names from diff headers.
++oo Do not remove files that are empty after patching.
++oo Do not ask whether to get files from RCS, ClearCase, Perforce, or
SCCS.
++oo Require that all options precede the files in the command line.
++oo Do not backup files when there is a mismatch.
--qquuoottiinngg-ssttyyllee==word
Use style word to quote output names. The word should be one of the
following:
lliitteerraall
Output names as-is.
sshheellll Quote names for the shell if they contain shell metacharac-
ters or would cause ambiguous output.
sshheellll-aallwwaayyss
Quote names for the shell, even if they would normally not
require quoting.
cc Quote names as for a C language string.
eessccaappee Quote as with cc except omit the surrounding double-quote
characters.
You can specify the default value of the --qquuoottiinngg-ssttyyllee option with
the environment variable QQUUOOTTIINNGGSSTTYYLLEE. If that environment vari-
able is not set, the default value is sshheellll.
-rr rejectfile or --rreejjeecctt-ffiillee==rejectfile
Put rejects into rejectfile instead of the default ..rreejj file.
-RR or --rreevveerrssee
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.) ppaattcchh attempts to swap each hunk around
before applying it. Rejects come out in the swapped format. The -RR
option does not work with eedd diff scripts because there is too lit-
tle information to reconstruct the reverse operation.
If the first hunk of a patch fails, ppaattcchh reverses the hunk to see
if it can be applied that way. If it can, you are asked if you want
to have the -RR 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.)
-ss or --ssiilleenntt or --qquuiieett
Work silently, unless an error occurs.
-tt or --bbaattcchh
Suppress questions like -ff, but make some different assumptions:
skip patches whose headers do not contain file names (the same as
-ff); skip patches for which the file has the wrong version for the
PPrreerreeqq:: line in the patch; and assume that patches are reversed if
they look like they are.
-TT or --sseett-ttiimmee
Set the modification and access times of patched files from time
stamps given in context 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, generate patches with UTC and use the
-ZZ or --sseett-uuttcc option instead.
-uu or --uunniiffiieedd
Interpret the patch file as a unified context diff.
-vv or --vveerrssiioonn
Print out ppaattcchh's revision header and patch level, and exit.
-VV method or --vveerrssiioonn-ccoonnttrrooll==method
Use method to determine backup file names. The method can also be
given by the PPAATTCCHHVVEERRSSIIOONNCCOONNTTRROOLL (or, if that's not set, the VVEERR-
SSIIOONNCCOONNTTRROOLL) 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' vari-
able; ppaattcchh also recognizes synonyms that are more descriptive. The
valid values for method are (unique abbreviations are accepted):
eexxiissttiinngg or nniill
Make numbered backups of files that already have them, otherwise
simple backups. This is the default.
nnuummbbeerreedd or tt
Make numbered backups. The numbered backup file name for F is
F..~~N~~ where N is the version number.
ssiimmppllee or nneevveerr
Make simple backups. The -BB or --pprreeffiixx, -YY or --bbaasseennaammee-pprree-
ffiixx, and -zz or --ssuuffffiixx 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 SSIIMMPPLLEEBBAACCKKUUPPSSUUFFFFIIXX envi-
ronment variable if set, and is ..oorriigg 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.
--vveerrbboossee
Output extra information about the work being done.
-xx num or --ddeebbuugg==num
Set internal debugging flags of interest only to ppaattcchh patchers.
-YY pref or --bbaasseennaammee-pprreeffiixx==pref
Prefix pref to the basename of a file name when generating its sim-
ple backup file name. For example, with -YY ..ddeell// the simple backup
file name for ssrrcc//ppaattcchh//uuttiill..cc is ssrrcc//ppaattcchh//..ddeell//uuttiill..cc.
-zz suffix or --ssuuffffiixx==suffix
Use suffix as the simple backup suffix. For example, with -zz - the
simple backup file name for ssrrcc//ppaattcchh//uuttiill..cc is ssrrcc//ppaattcchh//uuttiill..cc-.
The backup suffix may also be specified by the SSIIMMPPLLEEBBAACCKKUUPPSSUUFFFFIIXX
environment variable, which is overridden by this option.
-ZZ or --sseett-uuttcc
Set the modification and access times of patched files from time
stamps given in context diff headers, assuming that the context diff
headers use Coordinated Universal Time (UTC, often known as GMT).
Also see the -TT or --sseett-ttiimmee option.
The -ZZ or --sseett-uuttcc and -TT or --sseett-ttiimmee 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 -ff or --ffoorrccee option is
given, the file time is set regardless.
Due to the limitations of ddiiffff 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 mmaakkee cclleeaann) all
files that depend on the patched files, so that later invocations of
mmaakkee do not get confused by the patched files' times.
ENVIRONMENT PPAATTCCHHGGEETT
This specifies whether ppaattcchh gets missing or read-only files from
RCS, ClearCase, Perforce, or SCCS by default; see the -gg or --ggeett
option.
PPOOSSIIXXLLYYCCOORRRREECCTT
If set, ppaattcchh conforms more strictly to the POSIX standard by
default: see the --ppoossiixx option.
QQUUOOTTIINNGGSSTTYYLLEE
Default value of the --qquuoottiinngg-ssttyyllee option.
SSIIMMPPLLEEBBAACCKKUUPPSSUUFFFFIIXX
Extension to use for simple backup file names instead of ..oorriigg.
TTMMPPDDIIRR, TTMMPP, TTEEMMPP
Directory to put temporary files in; ppaattcchh uses the first environ-
ment variable in this list that is set. If none are set, the
default is system-dependent; it is normally //ttmmpp on Unix hosts.
VVEERRSSIIOONNCCOONNTTRROOLL or PPAATTCCHHVVEERRSSIIOONNCCOONNTTRROOLL
Selects version control style; see the -vv or --vveerrssiioonn-ccoonnttrrooll
option.
FILES $TMPDIR//pp**
temporary files
//ddeevv//ttttyy
controlling terminal; used to get answers to questions asked of the
user
SEE ALSO
ddiiffff(1), eedd(1)
Marshall T. Rose and Einar A. Stefferud, Proposed Standard for Message
Encapsulation, Internet RFC 934 notes/rfc934.txt> (1985-01).
NNOOTTEESS FFOORR PPAATTCCHH SSEENNDDEERRSS
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
ddiiffff -NNaauurr old new where old and new identify the old and new directo-
ries. The names old and new should not contain any slashes. The ddiiffff
command's headers should have dates and times in Universal Time using
traditional Unix format, so that patch recipients can use the -ZZ or
--sseett-uuttcc option. Here is an example command, using Bourne shell syn-
tax:
LLCCAALLLL==CC TTZZ==UUTTCC00 ddiiffff -NNaauurr ggcccc-22..77 ggcccc-22..88
Tell your recipients how to apply the patch by telling them which
directory to ccdd to, and which ppaattcchh options to use. The option string
-NNpp11 is recommended. Test your procedure by pretending to be a recipi-
ent and applying your patch to a copy of the original files.
You can save people a lot of grief by keeping a ppaattcchhlleevveell..hh file which
is patched to increment the patch level as the first diff in the patch
file you send out. If you put a PPrreerreeqq:: 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 //ddeevv//nnuullll 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
ppaattcchh is conforming to POSIX and the -EE or --rreemmoovvee-eemmppttyy-ffiilleess option
is not given. An easy way to generate patches that create and remove
files is to use GNU ddiiffff's -NN or --nneeww-ffiillee option.
If the recipient is supposed to use the -ppN option, do not send output
that looks like this:
ddiiffff -NNaauurr vv22..00..2299//pprroogg//RREEAADDMMEE pprroogg//RREEAADDMMEE
--- vv22..00..2299//pprroogg//RREEAADDMMEE MMoonn MMaarr 1100 1155::1133::1122 11999977
++++++ pprroogg//RREEAADDMMEE MMoonn MMaarr 1177 1144::5588::2222 11999977
because the two file names have different numbers of slashes, and dif-
ferent versions of ppaattcchh interpret the file names differently. To
avoid confusion, send output that looks like this instead:
ddiiffff -NNaauurr vv22..00..2299//pprroogg//RREEAADDMMEE vv22..00..3300//pprroogg//RREEAADDMMEE
--- vv22..00..2299//pprroogg//RREEAADDMMEE MMoonn MMaarr 1100 1155::1133::1122 11999977
++++++ vv22..00..3300//pprroogg//RREEAADDMMEE MMoonn MMaarr 1177 1144::5588::2222 11999977
Avoid sending patches that compare backup file names like RREEAADDMMEE..oorriigg,
since this might confuse ppaattcchh 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. oolldd//RREEAADDMMEE and nneeww//RREEAADDMMEE.
Take care not to send out reversed patches, since it makes people won-
der whether they already applied the patch.
Try not to have your patch modify derived files (e.g. the file ccoonnffiigg-
uurree where there is a line ccoonnffiigguurree:: ccoonnffiigguurree..iinn in your makefile),
since the recipient should be able to regenerate the derived files any-
way. If you must send diffs of derived files, generate the diffs using
UTC, have the recipients apply the patch with the -ZZ or --sseett-uuttcc
option, and have them remove any unpatched files that depend on patched
files (e.g. with mmaakkee cclleeaann).
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 ppaattcchh couldn't parse your patch
file.
If the --vveerrbboossee option is given, the message HHmmmm...... indicates that
there is unprocessed text in the patch file and that ppaattcchh is attempt-
ing to intuit whether there is a patch in that text and, if so, what
kind of patch it is.
ppaattcchh'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.
CCAAVVEEAATTSS
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.
ppaattcchh cannot tell if the line numbers are off in an eedd 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 prob-
lem. Until a suitable interactive interface is added, you should prob-
ably 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.
ppaattcchh 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.
CCOOMMPPAATTIIBBIILLIITTYY IISSSSUUEESS
The POSIX standard specifies behavior that differs from ppaattcchh's tradi-
tional behavior. You should be aware of these differences if you must
interoperate with ppaattcchh versions 2.1 and earlier, which do not conform
to POSIX.
++oo In traditional ppaattcchh, the -pp option's operand was optional, and a
bare -pp was equivalent to -pp00.. The -pp option now requires an oper-
and, and -pp 00 is now equivalent to -pp00. For maximum compatibility,
use options like -pp00 and -pp11.
Also, traditional ppaattcchh simply counted slashes when stripping path
prefixes; ppaattcchh 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.
++oo In traditional ppaattcchh, backups were enabled by default. This behav-
ior is now enabled with the -bb or --bbaacckkuupp option.
Conversely, in POSIX ppaattcchh, backups are never made, even when there
is a mismatch. In GNU ppaattcchh, this behavior is enabled with the
--nnoo-bbaacckkuupp-iiff-mmiissmmaattcchh option, or by conforming to POSIX with the
--ppoossiixx option or by setting the PPOOSSIIXXLLYYCCOORRRREECCTT environment vari-
able.
The -bb suffix option of traditional ppaattcchh is equivalent to the
-bb -zz suffix options of GNU ppaattcchh.
++oo Traditional ppaattcchh 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 ppaattcchh uses a different, equally complicated (but bet-
ter 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 IInnddeexx:: line are all identi-
cal after prefix-stripping. Your patch is normally compatible if
each header's file names all contain the same number of slashes.
++oo When traditional ppaattcchh asked the user a question, it sent the ques-
tion to standard error and looked for an answer from the first file
in the following list that was a terminal: standard error, standard
output, //ddeevv//ttttyy, and standard input. Now ppaattcchh sends questions to
standard output and gets answers from //ddeevv//ttttyy. Defaults for some
answers have been changed so that ppaattcchh never goes into an infinite
loop when using default answers.
++oo Traditional ppaattcchh exited with a status value that counted the number
of bad hunks, or with status 1 if there was real trouble. Now ppaattcchh
exits with status 1 if some hunks failed, or with 2 if there was
real trouble.
++oo Limit yourself to the following options when sending instructions
meant to be executed by anyone running GNU ppaattcchh, traditional ppaattcchh,
or a ppaattcchh that conforms to POSIX. Spaces are significant in the
following list, and operands are required.
-cc
-dd dir
-DD define
-ee
-ll
-nn
-NN
-oo outfile
-ppnum
-RR
-rr rejectfile
BUGS
Please report bugs via email to <>.
ppaattcchh could be smarter about partial matches, excessively deviant off-
sets and swapped code, but that would take an extra pass.
If code has been duplicated (for instance with ##iiffddeeff OOLLDDCCOODDEE ... ##eellssee
...... ##eennddiiff), ppaattcchh 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, ppaattcchh thinks it is a
reversed patch, and offers to un-apply the patch. This could be con-
strued as a feature.
CCOOPPYYIINNGG
Copyright (C) 1984, 1985, 1986, 1988 Larry Wall.
Copyright (C) 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
1998, 1999, 2000, 2001, 2002 Free Software Foundation, 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 distributed under the terms of a per-
mission notice identical to this one.
Permission is granted to copy and distribute translations of this man-
ual into another language, under the above conditions for modified ver-
sions, except that this permission notice may be included in transla-
tions approved by the copyright holders instead of in the original
English.
AUTHORS Larry Wall wrote the original version of ppaattcchh. Paul Eggert removed
ppaattcchh'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 2003/05/08 PATCH(1)