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Introduction | Get the Software | Reporting Bugs
Computer users often find occasion to ask how two files differ. Perhaps one file is a newer version of the other file. Or maybe the two files started out as identical copies but were changed by different people.
You can use the diff command to show differences between
two files, or each corresponding file in two directories.
diff outputs differences between files line by line in
any of several formats, selectable by command line options. This set
of differences is often called a `diff' or `patch'. For files that are
identical, diff normally produces no output; for binary
(non-text) files, diff normally reports only that they
are different.
You can use the cmp command to show the offsets and line
numbers where two files differ. cmp can also show all the
characters that differ between the two files, side by side.
You can use the diff3 command to show differences among
three files. When two people have made independent changes to a common
original, diff3 can report the differences between the
original and the two changed versions, and can produce a merged file
that contains both persons' changes together with warnings about
conflicts.
You can use the sdiff command to merge two files interactively.
The Diffutils manual is available.
Diffutils can be found in the directory http://ftp.gnu.org/pub/gnu/diffutils/ or from a GNU FTP Mirror Site. Test releases, which should not be used in production, are available in the directory ftp://alpha.gnu.org/pub/gnu/diffutils/. The latest publicly-available sources, which are even more bleeding-edge than the test releases, can be found in the Savannah public area for Diffutils. For other ways to obtain Diffutils, please read How to get GNU Software.
diff --version and sample input files that
produce the bug, if applicable. If you have a patch, please send it
too. It may simplify the maintainer's job if the patch is relative to
the latest publicly-available sources or to a recent test release,
which you can find as described above.
Please send FSF & GNU inquiries & questions to <gnu@gnu.org>. There are also other ways to contact the FSF.
Please send comments on these web pages to <webmasters@gnu.org>, send other questions to <gnu@gnu.org>.
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Verbatim copying and distribution of this entire article is permitted in any medium, provided this notice is preserved.
Last updated: $Date: 2006/01/05 22:33:13 $ $Author: eggert $