How do you diff a directory for only files of a specific type?

Question

I have a question about the diff command if I want a recursive directory diff but only for a specific file type, how to do that?

I tried using the exclude option but can

Answer 1

I used the following command to find the diff of all *.tmpl files between DIR1 and DIR2. In my case this didn't yield any false positives, but it may for you, depending on the contents of your DIRS.

diff --brief DIR1 DIR2 | grep tmpl

Answer 2

Whilst it does not avoid the actual diff of other files, if your goal is to produce a patch file, or similar then you can use filterdiff from the patchutils package, e.g. to patch only your .py changes:

diff -ruNp /path/1 /path/2 | filterdiff -i "*.py" | tee /path/to/file.patch

Answer 3

Taken from ( a version of) the man page:

-x PAT  --exclude=PAT
  Exclude files that match PAT.

-X FILE    --exclude-from=FILE
  Exclude files that match any pattern in FILE.

So it looks like -x only accepts one pattern as you report but if you put all the patterns you want to exclude in a file (presumably one per line) you could use the second flag like so:

$ diff /destination/dir/1 /destination/dir/2 -r -X exclude.pats

where exclude.pats is:

*.jpg
*.JPG
*.xml
*.XML
*.png
*.gif

Answer 4

If you want to differ sources and keep it simple:

diff -rqx "*.a" -x "*.o" -x "*.d" ./PATH1 ./PATH2 | grep "\.cpp " | grep "^Files"

Remove the last grep if you want to get the files which exist in only one of the paths.

Answer 5

In case you find it convenient, you could use the following Makefile. Just run: "make patch"

#Makefile for patches

#Exlude following file endings
SUFFIX += o
SUFFIX += so
SUFFIX += exe
SUFFIX += pdf
SUFFIX += swp

#Exlude following folders
FOLDER += bin
FOLDER += lib
FOLDER += Image
FOLDER += models

OPTIONS = Naur

patch: 
    rm test.patch
    diff -$(OPTIONS) \
    $(foreach element, $(SUFFIX) , -x '*.$(element)') \
    $(foreach element, $(FOLDER) , -x '$(element)*') \
        org/ new/ > test.patch  

unpatch: 
    rm test.unpatch
    diff -$(OPTIONS) \
    $(foreach element, $(SUFFIX) , -x '*.$(element)') \
    $(foreach element, $(FOLDER) , -x '$(element)*') \
    new/ org/ > test.unpatch

Answer 6

You can specify -x more than once.

diff -x '*.foo' -x '*.bar' -x '*.baz' /destination/dir/1 /destination/dir/2

From the Comparing Directories section of info diff (on my system, I have to do info -f /usr/share/info/diff.info.gz):

To ignore some files while comparing directories, use the '-x PATTERN' or '--exclude=PATTERN' option. This option ignores any files or subdirectories whose base names match the shell pattern PATTERN. Unlike in the shell, a period at the start of the base of a file name matches a wildcard at the start of a pattern. You should enclose PATTERN in quotes so that the shell does not expand it. For example, the option -x '*.[ao]' ignores any file whose name ends with '.a' or '.o'.

This option accumulates if you specify it more than once. For example, using the options -x 'RCS' -x '*,v' ignores any file or subdirectory whose base name is 'RCS' or ends with ',v'.