-i --ignore-case Ignore case differences in file contents.
--ignore-file-name-case Ignore case when comparing file names.
--no-ignore-file-name-case 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-cr 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.
--normal 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.
--left-column Output only the left column of common lines.
--suppress-common-lines Do not output common lines.
-D NAME --ifdef=NAME Output merged file to show `#ifdef NAME' diffs.
--GTYPE-group-format=GFMT Similar, but format GTYPE input groups with GFMT.
--line-format=LFMT Similar, but format all input lines with LFMT.
--LTYPE-line-format=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
%[-][WIDTH][.[PREC]]{doxX}LETTER 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
%[-][WIDTH][.[PREC]]{doxX}n printf-style spec for input line number
Either GFMT or LFMT may contain:%% %
%c'C' the single character C
%c'\eOOO' 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.
--tabsize=NUM Tab stops are every NUM (default 8) print columns.
-r --recursive Recursively compare any subdirectories found.
-N --new-file Treat absent files as empty.
--unidirectional-new-file 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.
--from-file=FILE1 Compare FILE1 to all operands. FILE1 can be a directory.
--to-file=FILE2 Compare all operands to FILE2. FILE2 can be a directory.
--horizon-lines=NUM Keep NUM lines of the common prefix and suffix.
-d --minimal Try hard to find a smaller set of changes.
--speed-large-files 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. Exit status is 0 if inputs are the same, 1 if different, 2 if trouble.
This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
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