git-show - Show various types of objects


   git show [options] <object>...


   Shows one or more objects (blobs, trees, tags and commits).

   For commits it shows the log message and textual diff. It also presents
   the merge commit in a special format as produced by git diff-tree --cc.

   For tags, it shows the tag message and the referenced objects.

   For trees, it shows the names (equivalent to git ls-tree with

   For plain blobs, it shows the plain contents.

   The command takes options applicable to the git diff-tree command to
   control how the changes the commit introduces are shown.

   This manual page describes only the most frequently used options.


       The names of objects to show. For a more complete list of ways to
       spell object names, see "SPECIFYING REVISIONS" section in

   --pretty[=<format>], --format=<format>
       Pretty-print the contents of the commit logs in a given format,
       where <format> can be one of oneline, short, medium, full, fuller,
       email, raw, format:<string> and tformat:<string>. When <format> is
       none of the above, and has %placeholder in it, it acts as if
       --pretty=tformat:<format> were given.

       See the "PRETTY FORMATS" section for some additional details for
       each format. When =<format> part is omitted, it defaults to medium.

       Note: you can specify the default pretty format in the repository
       configuration (see git-config(1)).

       Instead of showing the full 40-byte hexadecimal commit object name,
       show only a partial prefix. Non default number of digits can be
       specified with "--abbrev=<n>" (which also modifies diff output, if
       it is displayed).

       This should make "--pretty=oneline" a whole lot more readable for
       people using 80-column terminals.

       Show the full 40-byte hexadecimal commit object name. This negates
       --abbrev-commit and those options which imply it such as
       "--oneline". It also overrides the log.abbrevCommit variable.

       This is a shorthand for "--pretty=oneline --abbrev-commit" used

       The commit objects record the encoding used for the log message in
       their encoding header; this option can be used to tell the command
       to re-code the commit log message in the encoding preferred by the
       user. For non plumbing commands this defaults to UTF-8. Note that
       if an object claims to be encoded in X and we are outputting in X,
       we will output the object verbatim; this means that invalid
       sequences in the original commit may be copied to the output.

   --expand-tabs=<n>, --expand-tabs, --no-expand-tabs
       Perform a tab expansion (replace each tab with enough spaces to
       fill to the next display column that is multiple of <n>) in the log
       message before showing it in the output.  --expand-tabs is a
       short-hand for --expand-tabs=8, and --no-expand-tabs is a
       short-hand for --expand-tabs=0, which disables tab expansion.

       By default, tabs are expanded in pretty formats that indent the log
       message by 4 spaces (i.e.  medium, which is the default, full, and

       Show the notes (see git-notes(1)) that annotate the commit, when
       showing the commit log message. This is the default for git log,
       git show and git whatchanged commands when there is no --pretty,
       --format, or --oneline option given on the command line.

       By default, the notes shown are from the notes refs listed in the
       core.notesRef and notes.displayRef variables (or corresponding
       environment overrides). See git-config(1) for more details.

       With an optional <treeish> argument, use the treeish to find the
       notes to display. The treeish can specify the full refname when it
       begins with refs/notes/; when it begins with notes/, refs/ and
       otherwise refs/notes/ is prefixed to form a full name of the ref.

       Multiple --notes options can be combined to control which notes are
       being displayed. Examples: "--notes=foo" will show only notes from
       "refs/notes/foo"; "--notes=foo --notes" will show both notes from
       "refs/notes/foo" and from the default notes ref(s).

       Do not show notes. This negates the above --notes option, by
       resetting the list of notes refs from which notes are shown.
       Options are parsed in the order given on the command line, so e.g.
       "--notes --notes=foo --no-notes --notes=bar" will only show notes
       from "refs/notes/bar".

   --show-notes[=<treeish>], --[no-]standard-notes
       These options are deprecated. Use the above --notes/--no-notes
       options instead.

       Check the validity of a signed commit object by passing the
       signature to gpg --verify and show the output.


   If the commit is a merge, and if the pretty-format is not oneline,
   email or raw, an additional line is inserted before the Author: line.
   This line begins with "Merge: " and the sha1s of ancestral commits are
   printed, separated by spaces. Note that the listed commits may not
   necessarily be the list of the direct parent commits if you have
   limited your view of history: for example, if you are only interested
   in changes related to a certain directory or file.

   There are several built-in formats, and you can define additional
   formats by setting a pretty.<name> config option to either another
   format name, or a format: string, as described below (see git-
   config(1)). Here are the details of the built-in formats:

   *   oneline

           <sha1> <title line>

       This is designed to be as compact as possible.

   *   short

           commit <sha1>
           Author: <author>

           <title line>

   *   medium

           commit <sha1>
           Author: <author>
           Date:   <author date>

           <title line>

           <full commit message>

   *   full

           commit <sha1>
           Author: <author>
           Commit: <committer>

           <title line>

           <full commit message>

   *   fuller

           commit <sha1>
           Author:     <author>
           AuthorDate: <author date>
           Commit:     <committer>
           CommitDate: <committer date>

           <title line>

           <full commit message>

   *   email

           From <sha1> <date>
           From: <author>
           Date: <author date>
           Subject: [PATCH] <title line>

           <full commit message>

   *   raw

       The raw format shows the entire commit exactly as stored in the
       commit object. Notably, the SHA-1s are displayed in full,
       regardless of whether --abbrev or --no-abbrev are used, and parents
       information show the true parent commits, without taking grafts or
       history simplification into account. Note that this format affects
       the way commits are displayed, but not the way the diff is shown
       e.g. with git log --raw. To get full object names in a raw diff
       format, use --no-abbrev.

   *   format:<string>

       The format:<string> format allows you to specify which information
       you want to show. It works a little bit like printf format, with
       the notable exception that you get a newline with %n instead of \n.

       E.g, format:"The author of %h was %an, %ar%nThe title was >>%s<<%n"
       would show something like this:

           The author of fe6e0ee was Junio C Hamano, 23 hours ago
           The title was >>t4119: test autocomputing -p<n> for traditional diff input.<<

       The placeholders are:

       *   %H: commit hash

       *   %h: abbreviated commit hash

       *   %T: tree hash

       *   %t: abbreviated tree hash

       *   %P: parent hashes

       *   %p: abbreviated parent hashes

       *   %an: author name

       *   %aN: author name (respecting .mailmap, see git-shortlog(1) or

       *   %ae: author email

       *   %aE: author email (respecting .mailmap, see git-shortlog(1) or

       *   %ad: author date (format respects --date= option)

       *   %aD: author date, RFC2822 style

       *   %ar: author date, relative

       *   %at: author date, UNIX timestamp

       *   %ai: author date, ISO 8601-like format

       *   %aI: author date, strict ISO 8601 format

       *   %cn: committer name

       *   %cN: committer name (respecting .mailmap, see git-shortlog(1)
           or git-blame(1))

       *   %ce: committer email

       *   %cE: committer email (respecting .mailmap, see git-shortlog(1)
           or git-blame(1))

       *   %cd: committer date (format respects --date= option)

       *   %cD: committer date, RFC2822 style

       *   %cr: committer date, relative

       *   %ct: committer date, UNIX timestamp

       *   %ci: committer date, ISO 8601-like format

       *   %cI: committer date, strict ISO 8601 format

       *   %d: ref names, like the --decorate option of git-log(1)

       *   %D: ref names without the " (", ")" wrapping.

       *   %e: encoding

       *   %s: subject

       *   %f: sanitized subject line, suitable for a filename

       *   %b: body

       *   %B: raw body (unwrapped subject and body)

       *   %N: commit notes

       *   %GG: raw verification message from GPG for a signed commit

       *   %G?: show "G" for a good (valid) signature, "B" for a bad
           signature, "U" for a good signature with unknown validity and
           "N" for no signature

       *   %GS: show the name of the signer for a signed commit

       *   %GK: show the key used to sign a signed commit

       *   %gD: reflog selector, e.g., refs/stash@{1} or refs/stash@{2
           minutes ago}; the format follows the rules described for the -g
           option. The portion before the @ is the refname as given on the
           command line (so git log -g refs/heads/master would yield

       *   %gd: shortened reflog selector; same as %gD, but the refname
           portion is shortened for human readability (so
           refs/heads/master becomes just master).

       *   %gn: reflog identity name

       *   %gN: reflog identity name (respecting .mailmap, see git-
           shortlog(1) or git-blame(1))

       *   %ge: reflog identity email

       *   %gE: reflog identity email (respecting .mailmap, see git-
           shortlog(1) or git-blame(1))

       *   %gs: reflog subject

       *   %Cred: switch color to red

       *   %Cgreen: switch color to green

       *   %Cblue: switch color to blue

       *   %Creset: reset color

       *   %C(...): color specification, as described under Values in the
           "CONFIGURATION FILE" section of git-config(1); adding auto, at
           the beginning will emit color only when colors are enabled for
           log output (by color.diff, color.ui, or --color, and respecting
           the auto settings of the former if we are going to a terminal).
           auto alone (i.e.  %C(auto)) will turn on auto coloring on the
           next placeholders until the color is switched again.

       *   %m: left (<), right (>) or boundary (-) mark

       *   %n: newline

       *   %%: a raw %

       *   %x00: print a byte from a hex code

       *   %w([<w>[,<i1>[,<i2>]]]): switch line wrapping, like the -w
           option of git-shortlog(1).

       *   %<(<N>[,trunc|ltrunc|mtrunc]): make the next placeholder take
           at least N columns, padding spaces on the right if necessary.
           Optionally truncate at the beginning (ltrunc), the middle
           (mtrunc) or the end (trunc) if the output is longer than N
           columns. Note that truncating only works correctly with N >= 2.

       *   %<|(<N>): make the next placeholder take at least until Nth
           columns, padding spaces on the right if necessary

       *   %>(<N>), %>|(<N>): similar to %<(<N>), %<|(<N>) respectively,
           but padding spaces on the left

       *   %>>(<N>), %>>|(<N>): similar to %>(<N>), %>|(<N>) respectively,
           except that if the next placeholder takes more spaces than
           given and there are spaces on its left, use those spaces

       *   %><(<N>), %><|(<N>): similar to % <(<N>), %<|(<N>)
           respectively, but padding both sides (i.e. the text is

       Some placeholders may depend on other options given to the revision
       traversal engine. For example, the %g* reflog options will insert
       an empty string unless we are traversing reflog entries (e.g., by
       git log -g). The %d and %D placeholders will use the "short"
       decoration format if --decorate was not already provided on the
       command line.

   If you add a + (plus sign) after % of a placeholder, a line-feed is
   inserted immediately before the expansion if and only if the
   placeholder expands to a non-empty string.

   If you add a - (minus sign) after % of a placeholder, line-feeds that
   immediately precede the expansion are deleted if and only if the
   placeholder expands to an empty string.

   If you add a ` ` (space) after % of a placeholder, a space is inserted
   immediately before the expansion if and only if the placeholder expands
   to a non-empty string.

   *   tformat:

       The tformat: format works exactly like format:, except that it
       provides "terminator" semantics instead of "separator" semantics.
       In other words, each commit has the message terminator character
       (usually a newline) appended, rather than a separator placed
       between entries. This means that the final entry of a single-line
       format will be properly terminated with a new line, just as the
       "oneline" format does. For example:

           $ git log -2 --pretty=format:%h 4da45bef \
             | perl -pe '$_ .= " -- NO NEWLINE\n" unless /\n/'
           7134973 -- NO NEWLINE

           $ git log -2 --pretty=tformat:%h 4da45bef \
             | perl -pe '$_ .= " -- NO NEWLINE\n" unless /\n/'

       In addition, any unrecognized string that has a % in it is
       interpreted as if it has tformat: in front of it. For example,
       these two are equivalent:

           $ git log -2 --pretty=tformat:%h 4da45bef
           $ git log -2 --pretty=%h 4da45bef


   -p, -u, --patch
       Generate patch (see section on generating patches).

   -s, --no-patch
       Suppress diff output. Useful for commands like git show that show
       the patch by default, or to cancel the effect of --patch.

   -U<n>, --unified=<n>
       Generate diffs with <n> lines of context instead of the usual
       three. Implies -p.

       For each commit, show a summary of changes using the raw diff
       format. See the "RAW OUTPUT FORMAT" section of git-diff(1). This is
       different from showing the log itself in raw format, which you can
       achieve with --format=raw.

       Synonym for -p --raw.

   --compaction-heuristic, --no-compaction-heuristic
       These are to help debugging and tuning an experimental heuristic
       (which is off by default) that shifts the hunk boundary in an
       attempt to make the resulting patch easier to read.

       Spend extra time to make sure the smallest possible diff is

       Generate a diff using the "patience diff" algorithm.

       Generate a diff using the "histogram diff" algorithm.

       Choose a diff algorithm. The variants are as follows:

       default, myers
           The basic greedy diff algorithm. Currently, this is the

           Spend extra time to make sure the smallest possible diff is

           Use "patience diff" algorithm when generating patches.

           This algorithm extends the patience algorithm to "support
           low-occurrence common elements".

       For instance, if you configured diff.algorithm variable to a
       non-default value and want to use the default one, then you have to
       use --diff-algorithm=default option.

       Generate a diffstat. By default, as much space as necessary will be
       used for the filename part, and the rest for the graph part.
       Maximum width defaults to terminal width, or 80 columns if not
       connected to a terminal, and can be overridden by <width>. The
       width of the filename part can be limited by giving another width
       <name-width> after a comma. The width of the graph part can be
       limited by using --stat-graph-width=<width> (affects all commands
       generating a stat graph) or by setting diff.statGraphWidth=<width>
       (does not affect git format-patch). By giving a third parameter
       <count>, you can limit the output to the first <count> lines,
       followed by ...  if there are more.

       These parameters can also be set individually with
       --stat-width=<width>, --stat-name-width=<name-width> and

       Similar to --stat, but shows number of added and deleted lines in
       decimal notation and pathname without abbreviation, to make it more
       machine friendly. For binary files, outputs two - instead of saying
       0 0.

       Output only the last line of the --stat format containing total
       number of modified files, as well as number of added and deleted

       Output the distribution of relative amount of changes for each
       sub-directory. The behavior of --dirstat can be customized by
       passing it a comma separated list of parameters. The defaults are
       controlled by the diff.dirstat configuration variable (see git-
       config(1)). The following parameters are available:

           Compute the dirstat numbers by counting the lines that have
           been removed from the source, or added to the destination. This
           ignores the amount of pure code movements within a file. In
           other words, rearranging lines in a file is not counted as much
           as other changes. This is the default behavior when no
           parameter is given.

           Compute the dirstat numbers by doing the regular line-based
           diff analysis, and summing the removed/added line counts. (For
           binary files, count 64-byte chunks instead, since binary files
           have no natural concept of lines). This is a more expensive
           --dirstat behavior than the changes behavior, but it does count
           rearranged lines within a file as much as other changes. The
           resulting output is consistent with what you get from the other
           --*stat options.

           Compute the dirstat numbers by counting the number of files
           changed. Each changed file counts equally in the dirstat
           analysis. This is the computationally cheapest --dirstat
           behavior, since it does not have to look at the file contents
           at all.

           Count changes in a child directory for the parent directory as
           well. Note that when using cumulative, the sum of the
           percentages reported may exceed 100%. The default
           (non-cumulative) behavior can be specified with the
           noncumulative parameter.

           An integer parameter specifies a cut-off percent (3% by
           default). Directories contributing less than this percentage of
           the changes are not shown in the output.

       Example: The following will count changed files, while ignoring
       directories with less than 10% of the total amount of changed
       files, and accumulating child directory counts in the parent
       directories: --dirstat=files,10,cumulative.

       Output a condensed summary of extended header information such as
       creations, renames and mode changes.

       Synonym for -p --stat.

       Separate the commits with NULs instead of with new newlines.

       Also, when --raw or --numstat has been given, do not munge
       pathnames and use NULs as output field terminators.

       Without this option, each pathname output will have TAB, LF, double
       quotes, and backslash characters replaced with \t, \n, \", and \\,
       respectively, and the pathname will be enclosed in double quotes if
       any of those replacements occurred.

       Show only names of changed files.

       Show only names and status of changed files. See the description of
       the --diff-filter option on what the status letters mean.

       Specify how differences in submodules are shown. When --submodule
       or --submodule=log is given, the log format is used. This format
       lists the commits in the range like git-submodule(1) summary does.
       Omitting the --submodule option or specifying --submodule=short,
       uses the short format. This format just shows the names of the
       commits at the beginning and end of the range. Can be tweaked via
       the diff.submodule configuration variable.

       Show colored diff.  --color (i.e. without =<when>) is the same as
       --color=always.  <when> can be one of always, never, or auto.

       Turn off colored diff. It is the same as --color=never.

       Show a word diff, using the <mode> to delimit changed words. By
       default, words are delimited by whitespace; see --word-diff-regex
       below. The <mode> defaults to plain, and must be one of:

           Highlight changed words using only colors. Implies --color.

           Show words as [-removed-] and {+added+}. Makes no attempts to
           escape the delimiters if they appear in the input, so the
           output may be ambiguous.

           Use a special line-based format intended for script
           consumption. Added/removed/unchanged runs are printed in the
           usual unified diff format, starting with a +/-/` ` character at
           the beginning of the line and extending to the end of the line.
           Newlines in the input are represented by a tilde ~ on a line of
           its own.

           Disable word diff again.

       Note that despite the name of the first mode, color is used to
       highlight the changed parts in all modes if enabled.

       Use <regex> to decide what a word is, instead of considering runs
       of non-whitespace to be a word. Also implies --word-diff unless it
       was already enabled.

       Every non-overlapping match of the <regex> is considered a word.
       Anything between these matches is considered whitespace and
       ignored(!) for the purposes of finding differences. You may want to
       append |[^[:space:]] to your regular expression to make sure that
       it matches all non-whitespace characters. A match that contains a
       newline is silently truncated(!) at the newline.

       For example, --word-diff-regex=.  will treat each character as a
       word and, correspondingly, show differences character by character.

       The regex can also be set via a diff driver or configuration
       option, see gitattributes(5) or git-config(1). Giving it explicitly
       overrides any diff driver or configuration setting. Diff drivers
       override configuration settings.

       Equivalent to --word-diff=color plus (if a regex was specified)

       Turn off rename detection, even when the configuration file gives
       the default to do so.

       Warn if changes introduce conflict markers or whitespace errors.
       What are considered whitespace errors is controlled by
       core.whitespace configuration. By default, trailing whitespaces
       (including lines that solely consist of whitespaces) and a space
       character that is immediately followed by a tab character inside
       the initial indent of the line are considered whitespace errors.
       Exits with non-zero status if problems are found. Not compatible
       with --exit-code.

       Highlight whitespace errors on lines specified by <kind> in the
       color specified by color.diff.whitespace. <kind> is a comma
       separated list of old, new, context. When this option is not given,
       only whitespace errors in new lines are highlighted. E.g.
       --ws-error-highlight=new,old highlights whitespace errors on both
       deleted and added lines.  all can be used as a short-hand for

       Instead of the first handful of characters, show the full pre- and
       post-image blob object names on the "index" line when generating
       patch format output.

       In addition to --full-index, output a binary diff that can be
       applied with git-apply.

       Instead of showing the full 40-byte hexadecimal object name in
       diff-raw format output and diff-tree header lines, show only a
       partial prefix. This is independent of the --full-index option
       above, which controls the diff-patch output format. Non default
       number of digits can be specified with --abbrev=<n>.

   -B[<n>][/<m>], --break-rewrites[=[<n>][/<m>]]
       Break complete rewrite changes into pairs of delete and create.
       This serves two purposes:

       It affects the way a change that amounts to a total rewrite of a
       file not as a series of deletion and insertion mixed together with
       a very few lines that happen to match textually as the context, but
       as a single deletion of everything old followed by a single
       insertion of everything new, and the number m controls this aspect
       of the -B option (defaults to 60%).  -B/70% specifies that less
       than 30% of the original should remain in the result for Git to
       consider it a total rewrite (i.e. otherwise the resulting patch
       will be a series of deletion and insertion mixed together with
       context lines).

       When used with -M, a totally-rewritten file is also considered as
       the source of a rename (usually -M only considers a file that
       disappeared as the source of a rename), and the number n controls
       this aspect of the -B option (defaults to 50%).  -B20% specifies
       that a change with addition and deletion compared to 20% or more of
       the file's size are eligible for being picked up as a possible
       source of a rename to another file.

   -M[<n>], --find-renames[=<n>]
       If generating diffs, detect and report renames for each commit. For
       following files across renames while traversing history, see
       --follow. If n is specified, it is a threshold on the similarity
       index (i.e. amount of addition/deletions compared to the file's
       size). For example, -M90% means Git should consider a delete/add
       pair to be a rename if more than 90% of the file hasn't changed.
       Without a % sign, the number is to be read as a fraction, with a
       decimal point before it. I.e., -M5 becomes 0.5, and is thus the
       same as -M50%. Similarly, -M05 is the same as -M5%. To limit
       detection to exact renames, use -M100%. The default similarity
       index is 50%.

   -C[<n>], --find-copies[=<n>]
       Detect copies as well as renames. See also --find-copies-harder. If
       n is specified, it has the same meaning as for -M<n>.

       For performance reasons, by default, -C option finds copies only if
       the original file of the copy was modified in the same changeset.
       This flag makes the command inspect unmodified files as candidates
       for the source of copy. This is a very expensive operation for
       large projects, so use it with caution. Giving more than one -C
       option has the same effect.

   -D, --irreversible-delete
       Omit the preimage for deletes, i.e. print only the header but not
       the diff between the preimage and /dev/null. The resulting patch is
       not meant to be applied with patch or git apply; this is solely for
       people who want to just concentrate on reviewing the text after the
       change. In addition, the output obviously lack enough information
       to apply such a patch in reverse, even manually, hence the name of
       the option.

       When used together with -B, omit also the preimage in the deletion
       part of a delete/create pair.

       The -M and -C options require O(n^2) processing time where n is the
       number of potential rename/copy targets. This option prevents
       rename/copy detection from running if the number of rename/copy
       targets exceeds the specified number.

       Select only files that are Added (A), Copied (C), Deleted (D),
       Modified (M), Renamed (R), have their type (i.e. regular file,
       symlink, submodule, ...) changed (T), are Unmerged (U), are Unknown
       (X), or have had their pairing Broken (B). Any combination of the
       filter characters (including none) can be used. When *
       (All-or-none) is added to the combination, all paths are selected
       if there is any file that matches other criteria in the comparison;
       if there is no file that matches other criteria, nothing is

       Also, these upper-case letters can be downcased to exclude. E.g.
       --diff-filter=ad excludes added and deleted paths.

       Look for differences that change the number of occurrences of the
       specified string (i.e. addition/deletion) in a file. Intended for
       the scripter's use.

       It is useful when you're looking for an exact block of code (like a
       struct), and want to know the history of that block since it first
       came into being: use the feature iteratively to feed the
       interesting block in the preimage back into -S, and keep going
       until you get the very first version of the block.

       Look for differences whose patch text contains added/removed lines
       that match <regex>.

       To illustrate the difference between -S<regex> --pickaxe-regex and
       -G<regex>, consider a commit with the following diff in the same

           +    return !regexec(regexp, two->ptr, 1, &regmatch, 0);
           -    hit = !regexec(regexp, mf2.ptr, 1, &regmatch, 0);

       While git log -G"regexec\(regexp" will show this commit, git log
       -S"regexec\(regexp" --pickaxe-regex will not (because the number of
       occurrences of that string did not change).

       See the pickaxe entry in gitdiffcore(7) for more information.

       When -S or -G finds a change, show all the changes in that
       changeset, not just the files that contain the change in <string>.

       Treat the <string> given to -S as an extended POSIX regular
       expression to match.

       Output the patch in the order specified in the <orderfile>, which
       has one shell glob pattern per line. This overrides the
       diff.orderFile configuration variable (see git-config(1)). To
       cancel diff.orderFile, use -O/dev/null.

       Swap two inputs; that is, show differences from index or on-disk
       file to tree contents.

       When run from a subdirectory of the project, it can be told to
       exclude changes outside the directory and show pathnames relative
       to it with this option. When you are not in a subdirectory (e.g. in
       a bare repository), you can name which subdirectory to make the
       output relative to by giving a <path> as an argument.

   -a, --text
       Treat all files as text.

       Ignore changes in whitespace at EOL.

   -b, --ignore-space-change
       Ignore changes in amount of whitespace. This ignores whitespace at
       line end, and considers all other sequences of one or more
       whitespace characters to be equivalent.

   -w, --ignore-all-space
       Ignore whitespace when comparing lines. This ignores differences
       even if one line has whitespace where the other line has none.

       Ignore changes whose lines are all blank.

       Show the context between diff hunks, up to the specified number of
       lines, thereby fusing hunks that are close to each other.

   -W, --function-context
       Show whole surrounding functions of changes.

       Allow an external diff helper to be executed. If you set an
       external diff driver with gitattributes(5), you need to use this
       option with git-log(1) and friends.

       Disallow external diff drivers.

   --textconv, --no-textconv
       Allow (or disallow) external text conversion filters to be run when
       comparing binary files. See gitattributes(5) for details. Because
       textconv filters are typically a one-way conversion, the resulting
       diff is suitable for human consumption, but cannot be applied. For
       this reason, textconv filters are enabled by default only for git-
       diff(1) and git-log(1), but not for git-format-patch(1) or diff
       plumbing commands.

       Ignore changes to submodules in the diff generation. <when> can be
       either "none", "untracked", "dirty" or "all", which is the default.
       Using "none" will consider the submodule modified when it either
       contains untracked or modified files or its HEAD differs from the
       commit recorded in the superproject and can be used to override any
       settings of the ignore option in git-config(1) or gitmodules(5).
       When "untracked" is used submodules are not considered dirty when
       they only contain untracked content (but they are still scanned for
       modified content). Using "dirty" ignores all changes to the work
       tree of submodules, only changes to the commits stored in the
       superproject are shown (this was the behavior until 1.7.0). Using
       "all" hides all changes to submodules.

       Show the given source prefix instead of "a/".

       Show the given destination prefix instead of "b/".

       Do not show any source or destination prefix.

   For more detailed explanation on these common options, see also


   When "git-diff-index", "git-diff-tree", or "git-diff-files" are run
   with a -p option, "git diff" without the --raw option, or "git log"
   with the "-p" option, they do not produce the output described above;
   instead they produce a patch file. You can customize the creation of
   such patches via the GIT_EXTERNAL_DIFF and the GIT_DIFF_OPTS
   environment variables.

   What the -p option produces is slightly different from the traditional
   diff format:

    1. It is preceded with a "git diff" header that looks like this:

           diff --git a/file1 b/file2

       The a/ and b/ filenames are the same unless rename/copy is
       involved. Especially, even for a creation or a deletion, /dev/null
       is not used in place of the a/ or b/ filenames.

       When rename/copy is involved, file1 and file2 show the name of the
       source file of the rename/copy and the name of the file that
       rename/copy produces, respectively.

    2. It is followed by one or more extended header lines:

           old mode <mode>
           new mode <mode>
           deleted file mode <mode>
           new file mode <mode>
           copy from <path>
           copy to <path>
           rename from <path>
           rename to <path>
           similarity index <number>
           dissimilarity index <number>
           index <hash>..<hash> <mode>

       File modes are printed as 6-digit octal numbers including the file
       type and file permission bits.

       Path names in extended headers do not include the a/ and b/

       The similarity index is the percentage of unchanged lines, and the
       dissimilarity index is the percentage of changed lines. It is a
       rounded down integer, followed by a percent sign. The similarity
       index value of 100% is thus reserved for two equal files, while
       100% dissimilarity means that no line from the old file made it
       into the new one.

       The index line includes the SHA-1 checksum before and after the
       change. The <mode> is included if the file mode does not change;
       otherwise, separate lines indicate the old and the new mode.

    3. TAB, LF, double quote and backslash characters in pathnames are
       represented as \t, \n, \" and \\, respectively. If there is need
       for such substitution then the whole pathname is put in double

    4. All the file1 files in the output refer to files before the commit,
       and all the file2 files refer to files after the commit. It is
       incorrect to apply each change to each file sequentially. For
       example, this patch will swap a and b:

           diff --git a/a b/b
           rename from a
           rename to b
           diff --git a/b b/a
           rename from b
           rename to a


   Any diff-generating command can take the -c or --cc option to produce a
   combined diff when showing a merge. This is the default format when
   showing merges with git-diff(1) or git-show(1). Note also that you can
   give the -m option to any of these commands to force generation of
   diffs with individual parents of a merge.

   A combined diff format looks like this:

       diff --combined describe.c
       index fabadb8,cc95eb0..4866510
       --- a/describe.c
       +++ b/describe.c
       @@@ -98,20 -98,12 +98,20 @@@
               return (a_date > b_date) ? -1 : (a_date == b_date) ? 0 : 1;

       - static void describe(char *arg)
        -static void describe(struct commit *cmit, int last_one)
       ++static void describe(char *arg, int last_one)
        +      unsigned char sha1[20];
        +      struct commit *cmit;
               struct commit_list *list;
               static int initialized = 0;
               struct commit_name *n;

        +      if (get_sha1(arg, sha1) < 0)
        +              usage(describe_usage);
        +      cmit = lookup_commit_reference(sha1);
        +      if (!cmit)
        +              usage(describe_usage);
               if (!initialized) {
                       initialized = 1;

    1. It is preceded with a "git diff" header, that looks like this (when
       -c option is used):

           diff --combined file

       or like this (when --cc option is used):

           diff --cc file

    2. It is followed by one or more extended header lines (this example
       shows a merge with two parents):

           index <hash>,<hash>..<hash>
           mode <mode>,<mode>..<mode>
           new file mode <mode>
           deleted file mode <mode>,<mode>

       The mode <mode>,<mode>..<mode> line appears only if at least one of
       the <mode> is different from the rest. Extended headers with
       information about detected contents movement (renames and copying
       detection) are designed to work with diff of two <tree-ish> and are
       not used by combined diff format.

    3. It is followed by two-line from-file/to-file header

           --- a/file
           +++ b/file

       Similar to two-line header for traditional unified diff format,
       /dev/null is used to signal created or deleted files.

    4. Chunk header format is modified to prevent people from accidentally
       feeding it to patch -p1. Combined diff format was created for
       review of merge commit changes, and was not meant for apply. The
       change is similar to the change in the extended index header:

           @@@ <from-file-range> <from-file-range> <to-file-range> @@@

       There are (number of parents + 1) @ characters in the chunk header
       for combined diff format.

   Unlike the traditional unified diff format, which shows two files A and
   B with a single column that has - (minus --- appears in A but removed in
   B), + (plus --- missing in A but added to B), or " " (space --- unchanged)
   prefix, this format compares two or more files file1, file2,... with
   one file X, and shows how X differs from each of fileN. One column for
   each of fileN is prepended to the output line to note how X's line is
   different from it.

   A - character in the column N means that the line appears in fileN but
   it does not appear in the result. A + character in the column N means
   that the line appears in the result, and fileN does not have that line
   (in other words, the line was added, from the point of view of that

   In the above example output, the function signature was changed from
   both files (hence two - removals from both file1 and file2, plus ++ to
   mean one line that was added does not appear in either file1 or file2).
   Also eight other lines are the same from file1 but do not appear in
   file2 (hence prefixed with +).

   When shown by git diff-tree -c, it compares the parents of a merge
   commit with the merge result (i.e. file1..fileN are the parents). When
   shown by git diff-files -c, it compares the two unresolved merge
   parents with the working tree file (i.e. file1 is stage 2 aka "our
   version", file2 is stage 3 aka "their version").


   git show v1.0.0
       Shows the tag v1.0.0, along with the object the tags points at.

   git show v1.0.0^{tree}
       Shows the tree pointed to by the tag v1.0.0.

   git show -s --format=%s v1.0.0^{commit}
       Shows the subject of the commit pointed to by the tag v1.0.0.

   git show next~10:Documentation/README
       Shows the contents of the file Documentation/README as they were
       current in the 10th last commit of the branch next.

   git show master:Makefile master:t/Makefile
       Concatenates the contents of said Makefiles in the head of the
       branch master.


   Git is to some extent character encoding agnostic.

   *   The contents of the blob objects are uninterpreted sequences of
       bytes. There is no encoding translation at the core level.

   *   Path names are encoded in UTF-8 normalization form C. This applies
       to tree objects, the index file, ref names, as well as path names
       in command line arguments, environment variables and config files
       (.git/config (see git-config(1)), gitignore(5), gitattributes(5)
       and gitmodules(5)).

       Note that Git at the core level treats path names simply as
       sequences of non-NUL bytes, there are no path name encoding
       conversions (except on Mac and Windows). Therefore, using non-ASCII
       path names will mostly work even on platforms and file systems that
       use legacy extended ASCII encodings. However, repositories created
       on such systems will not work properly on UTF-8-based systems (e.g.
       Linux, Mac, Windows) and vice versa. Additionally, many Git-based
       tools simply assume path names to be UTF-8 and will fail to display
       other encodings correctly.

   *   Commit log messages are typically encoded in UTF-8, but other
       extended ASCII encodings are also supported. This includes
       ISO-8859-x, CP125x and many others, but not UTF-16/32, EBCDIC and
       CJK multi-byte encodings (GBK, Shift-JIS, Big5, EUC-x, CP9xx etc.).

   Although we encourage that the commit log messages are encoded in
   UTF-8, both the core and Git Porcelain are designed not to force UTF-8
   on projects. If all participants of a particular project find it more
   convenient to use legacy encodings, Git does not forbid it. However,
   there are a few things to keep in mind.

    1. git commit and git commit-tree issues a warning if the commit log
       message given to it does not look like a valid UTF-8 string, unless
       you explicitly say your project uses a legacy encoding. The way to
       say this is to have i18n.commitencoding in .git/config file, like

                   commitencoding = ISO-8859-1

       Commit objects created with the above setting record the value of
       i18n.commitencoding in its encoding header. This is to help other
       people who look at them later. Lack of this header implies that the
       commit log message is encoded in UTF-8.

    2. git log, git show, git blame and friends look at the encoding
       header of a commit object, and try to re-code the log message into
       UTF-8 unless otherwise specified. You can specify the desired
       output encoding with i18n.logoutputencoding in .git/config file,
       like this:

                   logoutputencoding = ISO-8859-1

       If you do not have this configuration variable, the value of
       i18n.commitencoding is used instead.

   Note that we deliberately chose not to re-code the commit log message
   when a commit is made to force UTF-8 at the commit object level,
   because re-coding to UTF-8 is not necessarily a reversible operation.


   Part of the git(1) suite


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