Applying a single patch to files in multiple directories

Question

Directory structures looks like this:

orig/l1/l2/file2patch

orig/l1-2/file2patch

Diff'd with

new/l1/l2/file2patch

new/l1-2/file2patch

I get the correct diff between these files and save it in a file but applying it has proved to be non-trivial.

I've tried patch -d orig/ < patch.diff but the -d expects the files that are to be patched should live immediately in orig

Is there some way I can have patch recur on a directory and apply the patch to the specified files that exist in the patch?

Solution

While the given pathnames do not look quite right (especially the new tree, which someone else has changed), you can keep in mind that the patch program can be told to ignore a given number of levels of directory from the output of diff using the -p option.

When applying a patch to files in a different directory than the patch-file shows, you would cd into the directory (to cancel one part of the mismatch) and use the -p option to adjust for the cd.

Here is a short script illustrating how I would solve this (using the dry-run option of GNU patch for a simple listing):

#!/bin/sh
cd /tmp/foo
OUT=/tmp/patch.diff
rm -f $OUT
diff -u orig/l1/l2/file2patch new/l1/l2/file2patch >>$OUT
diff -u orig/l1-2/file2patch new/l1-2/file2patch >>$OUT

diffstat -p1 $OUT
cd orig
patch -p1 --dry-run <$OUT

Inputs:

$ find . -type f
./new/l1/l2/file2patch
./new/l1-2/file2patch
./orig/l1/l2/file2patch
./orig/l1-2/file2patch

Output:

$ /tmp/xx
 l1-2/file2patch  |   19 +++++++++++++------
 l1/l2/file2patch |    5 ++---
 2 files changed, 15 insertions(+), 9 deletions(-)
/tmp/foo/orig
patching file l1/l2/file2patch
patching file l1-2/file2patch

Further reading:

• diff - compare two files (POSIX)
• patch - apply changes to files (POSIX)
• diffstat - make histogram from diff-output

Comments

[Jeff Schaller]

Look into the -p flag to tell patch your directory structure is different

[cbrad]

@JeffSchaller I have two different directories that have two different levels.

[Alen Milakovic]

@cbrad You misunderstand what the -p flag does. Read man patch, specifically the -p option.