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Commands using diff

Commands using diff from sorted by
Terminal - Commands using diff - 88 results
diff -U99999 original.css modified.css | awk '/^-/{next} {f=f"\n"$0} /^\+.*[^ ]/{yes=1} /}/ {if(yes){print f} f="";yes=0}'
2012-01-12 07:57:22
User: unhammer
Functions: awk diff
0

This will extract the differing CSS entries of two files. I've left the initial character (plus or space) in output to show the real differing line, remove the initial character to get a working CSS file. The output CSS file is usable by either adding it in a below the to original.css, or by only using the output but adding @import url("original.css"); in the beginning.

This is very useful for converting Wordpress theme copies into real Wordpress child themes.

Could exclude common lines within entries too, I guess, but that might not be worth the complexity.

for f in $(ls -A ./dir); do echo -n $f && diff original.txt ./dir/$f | wc -l ; done | perl -ne 'my $h={}; while (<>) { chomp; if (/^(\S+?)\s*(\d+?)$/){$h->{$1}=$2;} }; for my $k (sort { $h->{$a} $h->{$b} } keys %$h ){ print "$k\t$h->{$k}\n"}'
diff -ru originDir updateDir > result.patch
diff -r -u originDir updateDir > result.patch
diffxml() { diff -wb <(xmllint --format "$1") <(xmllint --format "$2"); }
2011-10-06 07:36:13
User: sharfah
Functions: diff
Tags: diff xml xmllint
13

Diffs two xml files by formatting them first using xmllint and then invoking diff.

Usage: diffxml XMLFile1 XMLFile2

diff -U 9999 file_a file_b | tail -n +3 | grep -P "^(\ Header|\-|\+)"
2011-09-21 21:33:40
User: nnutter
Functions: diff grep tail
Tags: diff
0

Maybe very limited in its applicability but could be of use at times.

LC_ALL=C diff -q dir1 dir2 | grep differ | awk '{ print $2, $4 }' | xargs -n 2 gvim --nofork -d
2011-09-06 11:50:33
User: brock
Functions: awk diff grep xargs
0

LC_ALL=C is here to always grep on "differ" whatever your language env.

xargs -n 2 to run gvim -d with 2 arguments

gvim --nofork to use only one instance of gvim

diff rpm_output_from_other_computer <(rpm -qa|sort)
2011-06-25 11:45:15
User: xeor
Functions: diff rpm
0

Description is moved to "Sample output" because the html sanitizer for commandlinefu breaks the examples..

diff --changed-group-format='differs from line %dF to line %dL|' --unchanged-line-format='' $FILE1 $FILE2 | sed 's/|/\n/'
2011-06-02 15:04:36
User: dullgiulio
Functions: diff sed
-1

Using sed to print newlines as doing it in one line with diff is non-trivial.

Diff files over SSH: ssh [login]@[host] "cat [remote file]" | diff - "[local file]"
2011-04-28 16:59:56
User: dennisfaust
Functions: diff ssh
3

Sometimes you need to compare two config files on different servers. Put the file names into the above script and let 'er rip.

svn diff -r 1792:HEAD --summarize | awk '{if ($1 != "D") print $2}'| xargs -I {} tar rf incremental_release.tar {}
2011-04-05 15:00:49
User: windfold
Functions: awk diff tar xargs
Tags: bash svn awk xargs tar
0

The result of this command is a tar with all files that have been modified/added since revision 1792 until HEAD. This command is super useful for incremental releases.

svn diff -r M:N file.php | patch -p0
2011-03-29 04:15:02
User: ruslan
Functions: diff patch
1

M - current revision, N - older revision

diff -Naur --strip-trailing-cr
2011-02-10 14:32:42
User: ruslan
Functions: diff
2

This form is used in patches, svn, git etc. And I've created an alias for it:

alias diff='diff -Naur --strip-trailing-cr'

The latter option is especially useful, when somebody in team works in Windows; could be also used in commands like

svn diff --diff-cmd 'diff --strip-trailing-cr'...
svn diff --diff-cmd="colordiff"
2011-02-10 14:27:55
User: ruslan
Functions: diff
1

If colordiff utility installed, it is sometimes handy to call this command. Of course, you should create an alias for it. E.g. svndiff.

hg diff -c $REV --reverse | hg patch --no-commit -
diff <(lsusb) <(sleep 3s && lsusb)
2010-12-27 22:46:54
User: Juluan
Functions: diff sleep
23

I often use it to find recently added ou removed device, or using find in /dev, or anything similar.

Just run the command, plug the device, and wait to see him and only him

diff <(md5sum render_pack.zip| cut -d " " -f 1) <(md5sum /media/green/render_pack.zip| cut -d " " -f 1);echo $?
2010-12-27 18:29:00
User: schmiddim
Functions: cut diff echo md5sum
1

I had the problem that the Md5 Sum of a file changed after copying it to my external disk.

This unhandy command helped me to fix the problem.

diff -ua <(w3m -dump http://www.php.net/downloads.php|fgrep -A1 '5.2.15 (tar.bz2)'|awk '/md5:/{print $2}') <(md5sum php-5.2.15.tar.bz2|awk '{print $1}')
2010-12-10 11:31:07
User: sugitaro
Functions: awk diff fgrep md5sum
0

Use zsh process substitution syntax.

diff <(wget -q -O - URL1) <(wget -q -O - URL2)
diff <(ssh user@host1 cat /path/to/file) <(ssh user@host2 cat /path/to/file2)
hg diff -r$((`hg -q par | cut -d":" -f1`-1))
diff -b $file1 $file2 # GNU Tools
diff <(perl -wpl -e '$_ =~ s/^\s+|\s+$//g ;' file1) <(perl -wpl -e '$_ =~ s/^\s+|\s+$//g ;' file2)
2010-10-06 19:14:42
User: jemptymethod
Functions: diff perl
Tags: bash diff perl
2

**NOTE** Tekhne's alternative is much more succinct and its output conforms to the files actual contents rather than with white space removed

My command on the other hand uses bash process substitution (and "Minimal" Perl), instead of files, to first remove leading and trailing white space from lines, before diff'ing the streams. Very useful when differences in indentation, such as in programming source code files, may be irrelevant

HTMLTEXT=$( curl -s http://www.page.de/test.html > /tmp/new.html ; diff /tmp/new.html /tmp/old.html ); if [ "x$HTMLTEXT" != x ] ; then echo $HTMLTEXT | mail -s "Page has changed." mail@mail.de ; fi ; mv /tmp/new.html /tmp/old.html
2010-07-04 21:45:37
User: Emzy
Functions: diff echo mail mv
2

Checks if a web page has changed. Put it into cron to check periodically.

Change http://www.page.de/test.html and mail@mail.de for your needs.