diffutils: diff Options
13.1 Options to 'diff'
======================
Below is a summary of all of the options that GNU 'diff' accepts. Most
options have two equivalent names, one of which is a single letter
preceded by '-', and the other of which is a long name preceded by '--'.
Multiple single letter options (unless they take an argument) can be
combined into a single command line word: '-ac' is equivalent to '-a
-c'. Long named options can be abbreviated to any unique prefix of
their name. Brackets ([ and ]) indicate that an option takes an
optional argument.
'-a'
'--text'
Treat all files as text and compare them line-by-line, even if they
do not seem to be text. ⇒Binary.
'-b'
'--ignore-space-change'
Ignore changes in amount of white space. ⇒White Space.
'-B'
'--ignore-blank-lines'
Ignore changes that just insert or delete blank lines. ⇒Blank
Lines.
'--binary'
Read and write data in binary mode. ⇒Binary.
'-c'
Use the context output format, showing three lines of context.
⇒Context Format.
'--color [=WHEN]'
Specify whether to use color for distinguishing different contexts,
like header, added or removed lines. WHEN may be omitted, or one
of:
* none Do not use color at all. This is the default when no
-color option is specified.
* auto Use color only if standard output is a terminal.
* always Always use color.
Specifying '--color' and no WHEN is equivalent to '--color=auto'.
'-C LINES'
'--context[=LINES]'
Use the context output format, showing LINES (an integer) lines of
context, or three if LINES is not given. ⇒Context Format.
For proper operation, 'patch' typically needs at least two lines of
context.
For compatibility 'diff' also supports an obsolete option syntax
'-LINES' that has effect when combined with '-c', '-p', or '-u'.
New scripts should use '-U LINES' ('-C LINES') instead.
'--changed-group-format=FORMAT'
Use FORMAT to output a line group containing differing lines from
both files in if-then-else format. ⇒Line Group Formats.
'-d'
'--minimal'
Change the algorithm perhaps find a smaller set of changes. This
makes 'diff' slower (sometimes much slower). ⇒diff
Performance.
'-D NAME'
'--ifdef=NAME'
Make merged '#ifdef' format output, conditional on the preprocessor
macro NAME. ⇒If-then-else.
'-e'
'--ed'
Make output that is a valid 'ed' script. ⇒ed Scripts.
'-E'
'--ignore-tab-expansion'
Ignore changes due to tab expansion. ⇒White Space.
'-f'
'--forward-ed'
Make output that looks vaguely like an 'ed' script but has changes
in the order they appear in the file. ⇒Forward ed.
'-F REGEXP'
'--show-function-line=REGEXP'
In context and unified format, for each hunk of differences, show
some of the last preceding line that matches REGEXP. ⇒
Specified Headings.
'--from-file=FILE'
Compare FILE to each operand; FILE may be a directory.
'--help'
Output a summary of usage and then exit.
'--horizon-lines=LINES'
Do not discard the last LINES lines of the common prefix and the
first LINES lines of the common suffix. ⇒diff Performance.
'-i'
'--ignore-case'
Ignore changes in case; consider upper- and lower-case letters
equivalent. ⇒Case Folding.
'-I REGEXP'
'--ignore-matching-lines=REGEXP'
Ignore changes that just insert or delete lines that match REGEXP.
⇒Specified Lines.
'--ignore-file-name-case'
Ignore case when comparing file names. For example, recursive
comparison of 'd' to 'e' might compare the contents of 'd/Init' and
'e/inIt'. At the top level, 'diff d inIt' might compare the
contents of 'd/Init' and 'inIt'. ⇒Comparing Directories.
'-l'
'--paginate'
Pass the output through 'pr' to paginate it. ⇒Pagination.
'-L LABEL'
'--label=LABEL'
Context Format::) and unified format (⇒Unified Format)
headers. ⇒RCS.
'--left-column'
Print only the left column of two common lines in side by side
format. ⇒Side by Side Format.
'--line-format=FORMAT'
Use FORMAT to output all input lines in if-then-else format. ⇒
Line Formats.
'-n'
'--rcs'
Output RCS-format diffs; like '-f' except that each command
specifies the number of lines affected. ⇒RCS.
'-N'
'--new-file'
If one file is missing, treat it as present but empty. ⇒
Comparing Directories.
'--new-group-format=FORMAT'
Use FORMAT to output a group of lines taken from just the second
file in if-then-else format. ⇒Line Group Formats.
'--new-line-format=FORMAT'
Use FORMAT to output a line taken from just the second file in
if-then-else format. ⇒Line Formats.
'--no-dereference'
Act on symbolic links themselves instead of what they point to.
Two symbolic links are deemed equal only when each points to
precisely the same name.
'--old-group-format=FORMAT'
Use FORMAT to output a group of lines taken from just the first
file in if-then-else format. ⇒Line Group Formats.
'--old-line-format=FORMAT'
Use FORMAT to output a line taken from just the first file in
if-then-else format. ⇒Line Formats.
'-p'
'--show-c-function'
Show which C function each change is in. ⇒C Function
Headings.
'--palette=PALETTE'
Specify what color palette to use when colored output is enabled.
It defaults to 'rs=0:hd=1:ad=32:de=31:ln=36' for red deleted lines,
green added lines, cyan line numbers, bold header.
Supported capabilities are as follows.
'ad=32'
SGR substring for added lines. The default is green
foreground.
'de=31'
SGR substring for deleted lines. The default is red
foreground.
'hd=1'
SGR substring for chunk header. The default is bold
foreground.
'ln=36'
SGR substring for line numbers. The default is cyan
foreground.
'-q'
'--brief'
Report only whether the files differ, not the details of the
differences. ⇒Brief.
'-r'
'--recursive'
When comparing directories, recursively compare any subdirectories
found. ⇒Comparing Directories.
'-s'
'--report-identical-files'
Report when two files are the same. ⇒Comparing Directories.
'-S FILE'
'--starting-file=FILE'
When comparing directories, start with the file FILE. This is used
for resuming an aborted comparison. ⇒Comparing Directories.
'--speed-large-files'
Use heuristics to speed handling of large files that have numerous
scattered small changes. ⇒diff Performance.
'--strip-trailing-cr'
Strip any trailing carriage return at the end of an input line.
⇒Binary.
'--suppress-common-lines'
Do not print common lines in side by side format. ⇒Side by
Side Format.
'-t'
'--expand-tabs'
Expand tabs to spaces in the output, to preserve the alignment of
tabs in the input files. ⇒Tabs.
'-T'
'--initial-tab'
Output a tab rather than a space before the text of a line in
normal or context format. This causes the alignment of tabs in the
line to look normal. ⇒Tabs.
'--tabsize=COLUMNS'
Assume that tab stops are set every COLUMNS (default 8) print
columns. ⇒Tabs.
'--suppress-blank-empty'
Suppress any blanks before newlines when printing the
representation of an empty line, when outputting normal, context,
or unified format. ⇒Trailing Blanks.
'--to-file=FILE'
Compare each operand to FILE; FILE may be a directory.
'-u'
Use the unified output format, showing three lines of context.
⇒Unified Format.
'--unchanged-group-format=FORMAT'
Use FORMAT to output a group of common lines taken from both files
in if-then-else format. ⇒Line Group Formats.
'--unchanged-line-format=FORMAT'
Use FORMAT to output a line common to both files in if-then-else
format. ⇒Line Formats.
'--unidirectional-new-file'
If a first file is missing, treat it as present but empty. ⇒
Comparing Directories.
'-U LINES'
'--unified[=LINES]'
Use the unified output format, showing LINES (an integer) lines of
context, or three if LINES is not given. ⇒Unified Format.
For proper operation, 'patch' typically needs at least two lines of
context.
On older systems, 'diff' supports an obsolete option '-LINES' that
Standards conformance::) does not allow this; use '-U LINES'
instead.
'-v'
'--version'
Output version information and then exit.
'-w'
'--ignore-all-space'
Ignore white space when comparing lines. ⇒White Space.
'-W COLUMNS'
'--width=COLUMNS'
Output at most COLUMNS (default 130) print columns per line in side
by side format. ⇒Side by Side Format.
'-x PATTERN'
'--exclude=PATTERN'
When comparing directories, ignore files and subdirectories whose
basenames match PATTERN. ⇒Comparing Directories.
'-X FILE'
'--exclude-from=FILE'
When comparing directories, ignore files and subdirectories whose
basenames match any pattern contained in FILE. ⇒Comparing
Directories.
'-y'
'--side-by-side'
Use the side by side output format. ⇒Side by Side Format.
'-Z'
'--ignore-trailing-space'
Ignore white space at line end. ⇒White Space.
Info Catalog
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