Bureaucrats, confirmed, Administrators
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add quick directory comparison
diff -rq -x .svn ./work/myproject/ ./work/myproject-copy2/
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=== Piping ===
The <code>diff</code> command is fast, but often the output is hard to read to find the exact difference. You might try piping the output of the diff command to a graphical tool:
<source lang="bash">
diff fileA fileB | kdiff3 -
</source>
By using the dash option to kdiff3, you're telling it to read from STDIN, so it uses the output of the former commands being piped to it.
Or, piping to <code>awk</code> to print a list of just what's in the 'left side'.
<source lang="bash">
diff --suppress-common-lines --side-by-side modules.list.a.txt modules.list.b.txt |awk '{print $1}'
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=== Process Substitution ===
By using process substitution, we can operate on the output of commands without the need for saving to a file.
<source lang="bash">
drush pml --status=enabled --pipe > modules.list.txt
# make a bunch of changes to what modules are enabled, perhaps restoring from a backup, and compare to our original list
diff --suppress-common-lines --side-by-side <(drush pml --status=enabled --pipe) modules.list.txt
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This technique comes in handy if you wish to compare two directories at their top level. The '''extensions''' directory, for example, in [[MediaWiki]] from two different installations:
<source lang="bash">
diff --suppress-common-lines --side-by-side <(ls -1 /var/www/wiki.example.net/www/w/extensions/) <(ls -1 /var/www/wiki.example.org/www/w/extensions/)
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=== Compressed files ===
<code>zdiff</code> is a tool that can be used directly on compressed files (like zcat, zgrep, etc.)
== KDiff3 ==