- When we pass <string, length> pair to functions, we should try to
pass them in that order.
+
+Writing Documentation:
+
+ Every user-visible change should be reflected in the documentation.
+ The same general rule as for code applies -- imitate the existing
+ conventions. A few commented examples follow to provide reference
+ when writing or modifying command usage strings and synopsis sections
+ in the manual pages:
+
+ Placeholders are enclosed in angle brackets:
+ <file>
+ --sort=<key>
+ --abbrev[=<n>]
+
+ Possibility of multiple occurences is indicated by three dots:
+ <file>...
+ (One or more of <file>.)
+
+ Optional parts are enclosed in square brackets:
+ [<extra>]
+ (Zero or one <extra>.)
+
+ --exec-path[=<path>]
+ (Option with an optional argument. Note that the "=" is inside the
+ brackets.)
+
+ [<patch>...]
+ (Zero or more of <patch>. Note that the dots are inside, not
+ outside the brackets.)
+
+ Multiple alternatives are indicated with vertical bar:
+ [-q | --quiet]
+ [--utf8 | --no-utf8]
+
+ Parentheses are used for grouping:
+ [(<rev>|<range>)...]
+ (Any number of either <rev> or <range>. Parens are needed to make
+ it clear that "..." pertains to both <rev> and <range>.)
+
+ [(-p <parent>)...]
+ (Any number of option -p, each with one <parent> argument.)
+
+ git remote set-head <name> (-a | -d | <branch>)
+ (One and only one of "-a", "-d" or "<branch>" _must_ (no square
+ brackets) be provided.)
+
+ And a somewhat more contrived example:
+ --diff-filter=[(A|C|D|M|R|T|U|X|B)...[*]]
+ Here "=" is outside the brackets, because "--diff-filter=" is a
+ valid usage. "*" has its own pair of brackets, because it can
+ (optionally) be specified only when one or more of the letters is
+ also provided.
SYNOPSIS
--------
-'git diff' [<common diff options>] <commit>{0,2} [--] [<path>...]
+[verse]
+'git diff' [options] [<commit>] [--] [<path>...]
+'git diff' [options] --cached [<commit>] [--] [<path>...]
+'git diff' [options] <commit> <commit> [--] [<path>...]
+'git diff' [options] [--no-index] [--] <path> <path>
DESCRIPTION
-----------
-Show changes between two trees, a tree and the working tree, a
-tree and the index file, or the index file and the working tree.
+Show changes between the working tree and the index or a tree, changes
+between the index and a tree, changes between two trees, or changes
+between two files on disk.
'git diff' [--options] [--] [<path>...]::
SYNOPSIS
--------
-'git difftool' [<options>] <commit>{0,2} [--] [<path>...]
+'git difftool' [<options>] [<commit> [<commit>]] [--] [<path>...]
DESCRIPTION
-----------
'git difftool' is a git command that allows you to compare and edit files
between revisions using common diff tools. 'git difftool' is a frontend
-to 'git diff' and accepts the same options and arguments.
+to 'git diff' and accepts the same options and arguments. See
+linkgit:git-diff[1].
OPTIONS
-------
};
static const char builtin_diff_usage[] =
-"git diff <options> <rev>{0,2} -- <path>*";
+"git diff [<options>] [<commit> [<commit>]] [--] [<path>...]";
static void stuff_change(struct diff_options *opt,
unsigned old_mode, unsigned new_mode,