to the original) and context diffs (where several lines surrounding the changes
are included). See the manpage for diff for more details.
+When GNU diff is available, the pumpkins would prefer you use C<-u -p>
+(--unified --show-c-function) as arguments for optimal control. The
+examples below will only use -u.
+
The preferred method for creating a unified diff suitable for feeding
to the patch program is:
% diff -bu a/file b/file
# show function name in every hunk (safer, more informative)
+ % diff -u -p old/file new/file
% diff -u -F '^[_a-zA-Z0-9]+ *(' old/file new/file
+ # show sub name in perl files and modules
+ % diff -u -F '^sub' old/file.pm new/file.pm
-=item Directories
+ # show header in doc patches
+ % diff -u -F '^=head' old/file.pod new/file.pod
-IMPORTANT: Patches should be generated from the source root directory, not
-from the directory that the patched file resides in. This ensures that the
-maintainer patches the proper file.
+=item Derived Files
Many files in the distribution are derivative--avoid patching them.
Patch the originals instead. Most utilities (like perldoc) are in
backup the entire directory tree (to $source_root.old/ for example). This
will allow C<diff -ruN old-dir new-dir> to create all the patches at once.
+=item Directories
+
+IMPORTANT: Patches should be generated from the source root directory, not
+from the directory that the patched file resides in. This ensures that the
+maintainer patches the proper file.
+
+For larger patches that are dealing with multiple files or
+directories, Johan Vromans has written a powerful utility: makepatch.
+See the JV directory on CPAN for the current version. If you have this
+program available, it is recommended to create a duplicate of the perl
+directory tree against which you are intending to provide a patch and
+let makepatch figure out all the changes you made to your copy of the
+sources. As perl comes with a MANIFEST file, you need not delete
+object files and other derivative files from the two directory trees,
+makepatch is smart about them.
+
+Say, you have created a directory perl-5.7.1@8685/ for the perl you
+are taking as the base and a directory perl-5.7.1@8685-withfoo/ where
+you have your changes, you would run makepatch as follows:
+
+ makepatch -oldman perl-5.7.1@8685/MANIFEST \
+ -newman perl-5.7.1@8685-withfoo/MANIFEST \
+ -diff "diff -u" \
+ perl-5.7.1@8685 perl-5.7.1@8685-withfoo
+
=item Try it yourself
Just to make sure your patch "works", be sure to apply it to the Perl
emacs MANIFEST
(make changes)
cd ..
- diff -c perl5.008_42/MANIFEST.old perl5.008_42/MANIFEST > mypatch
+ diff -c perl5.7.42/MANIFEST.old perl5.7.42/MANIFEST > mypatch
(testing the patch:)
- mv perl5.008_42/MANIFEST perl5.008_42/MANIFEST.new
- cp perl5.008_42/MANIFEST.old perl5.008_42/MANIFEST
+ mv perl5.7.42/MANIFEST perl5.7.42/MANIFEST.new
+ cp perl5.7.42/MANIFEST.old perl5.7.42/MANIFEST
patch -p < mypatch
(should succeed)
- diff perl5.008_42/MANIFEST perl5.008_42/MANIFEST.new
+ diff perl5.7.42/MANIFEST perl5.7.42/MANIFEST.new
(should produce no output)
=head2 Submitting your patch
=item Mailers
Please, please, please (get the point? 8-) don't use a mailer that
-word wraps your patch or that MIME encodes it. Both of these leave
-the patch essentially worthless to the maintainer.
+word wraps your patch. This leaves the patch essentially worthless
+to the maintainers.
+
+Unfortunately many mailers word wrap the main text of messages, but
+luckily you can usually send your patches as email attachments without
+them getting "helpfully" word wrapped.
-If you have no choice in mailers and no way to get your hands on a
-better one there is, of course, a perl solution. Just do this:
+If you have no choice in mailers and no way to get your hands on
+a better one, there is, of course, a Perl solution. Just do this:
perl -ne 'print pack("u*",$_)' patch > patch.uue
The subject line on your patch should read
- [PATCH 5.xxx_xx AREA] Description
+ [PATCH 5.x.x AREA] Description
where the x's are replaced by the appropriate version number.
The description should be a very brief but accurate summary of the
Examples:
- [PATCH 5.004_04 DOC] fix minor typos
+ [PATCH 5.6.4 DOC] fix minor typos
- [PATCH 5.004_99 CORE] New warning for foo() when frobbing
+ [PATCH 5.7.9 CORE] New warning for foo() when frobbing
- [PATCH 5.005_42 CONFIG] Added support for fribnatz 1.5
+ [PATCH 5.7.16 CONFIG] Added support for fribnatz 1.5
The name of the file being patched makes for a poor subject line if
no other descriptive text accompanies it.
the machine the patch was created on and the machine on which it is
being applied.
+Be sure to use the Larry Wall version of patch. Some Operating Systems
+(HP-UX amongst those) have a patch command that does something completely
+different. The correct version of patch will show Larry's name several
+times when invoked as patch --version.
+
=item Cut and paste
B<Never> cut and paste a patch into your editor. This usually clobbers
=head1 Last Modified
-Last modified 21 January 1999
+Last modified 22 August 2002
+H.Merijn Brand <h.m.brand@xs4all.nl>
+Prev modified 21 January 1999
Daniel Grisinger <dgris@dimensional.com>
=head1 Author and Copyright Information
-Copyright (c) 1998 Daniel Grisinger
+Copyright (c) 1998-2002 Daniel Grisinger
Adapted from a posting to perl5-porters by Tim Bunce (Tim.Bunce@ig.co.uk).