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DIFF(1)                                         User Commands                                        DIFF(1)

       diff - compare files line by line

       diff [OPTION]... FILES

       Compare files line by line.

       -i  --ignore-case
              Ignore case differences in file contents.

              Ignore case when comparing file names.

              Consider case when comparing file names.

       -E  --ignore-tab-expansion
              Ignore changes due to tab expansion.

       -b  --ignore-space-change
              Ignore changes in the amount of white space.

       -w  --ignore-all-space
              Ignore all white space.

       -B  --ignore-blank-lines
              Ignore changes whose lines are all blank.

       -I RE  --ignore-matching-lines=RE
              Ignore changes whose lines all match RE.

              Strip trailing carriage return on input.

       -a  --text
              Treat all files as text.

       -c  -C NUM  --context[=NUM]
              Output NUM (default 3) lines of copied context.

       -u  -U NUM  --unified[=NUM]
              Output NUM (default 3) lines of unified context.

       --label LABEL
              Use LABEL instead of file name.

       -p  --show-c-function
              Show which C function each change is in.

       -F RE  --show-function-line=RE
              Show the most recent line matching RE.

       -q  --brief
              Output only whether files differ.

       -e  --ed
              Output an ed script.

              Output a normal diff.

       -n  --rcs
              Output an RCS format diff.

       -y  --side-by-side
              Output in two columns.

       -W NUM  --width=NUM
              Output at most NUM (default 130) print columns.

              Output only the left column of common lines.

              Do not output common lines.

       -D NAME  --ifdef=NAME
              Output merged file to show `#ifdef NAME' diffs.

              Similar, but format GTYPE input groups with GFMT.

              Similar, but format all input lines with LFMT.

              Similar, but format LTYPE input lines with LFMT.

       LTYPE is `old', `new', or `unchanged'.
              GTYPE is LTYPE or `changed'.

              GFMT may contain:

       %<     lines from FILE1

       %>     lines from FILE2

       %=     lines common to FILE1 and FILE2

              printf-style spec for LETTER

              LETTERs are as follows for new group, lower case for old group:

       F      first line number

       L      last line number

       N      number of lines = L-F+1

       E      F-1

       M      L+1

              LFMT may contain:

       %L     contents of line

       %l     contents of line, excluding any trailing newline

              printf-style spec for input line number

              Either GFMT or LFMT may contain:

       %%     %

       %c'C'  the single character C

              the character with octal code OOO

       -l  --paginate
              Pass the output through `pr' to paginate it.

       -t  --expand-tabs
              Expand tabs to spaces in output.

       -T  --initial-tab
              Make tabs line up by prepending a tab.

       -r  --recursive
              Recursively compare any subdirectories found.

       -N  --new-file
              Treat absent files as empty.

              Treat absent first files as empty.

       -s  --report-identical-files
              Report when two files are the same.

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

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

       -S FILE  --starting-file=FILE
              Start with FILE when comparing directories.

              Compare FILE1 to all operands.  FILE1 can be a directory.

              Compare all operands to FILE2.  FILE2 can be a directory.

              Keep NUM lines of the common prefix and suffix.

       -d  --minimal
              Try hard to find a smaller set of changes.

              Assume large files and many scattered small changes.

       -v  --version
              Output version info.

       --help Output this help.

       FILES  are  `FILE1  FILE2'  or  `DIR1  DIR2'  or  `DIR  FILE...' or `FILE... DIR'.  If --from-file or
       --to-file is given, there are no restrictions on FILES.  If a FILE is `-', read standard input.

       Written by Paul Eggert, Mike Haertel, David Hayes, Richard Stallman, and Len Tower.

       Report bugs to <>.

       Copyright (C) 2002 Free Software Foundation, Inc.

       This program comes with NO WARRANTY, to the extent permitted by law.  You may redistribute copies  of
       this  program  under  the  terms of the GNU General Public License.  For more information about these
       matters, see the file named COPYING.

       The full documentation for diff is maintained as a Texinfo manual.  If the info and diff programs are
       properly installed at your site, the command

              info diff

       should give you access to the complete manual.

diffutils 2.8.1                                  April 2002                                          DIFF(1)

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