reftable: avoid undefined behaviour breaking t0032

[git/debian.git] / Documentation / git-config.txt

git-config(1)
=============

NAME
----
git-config - Get and set repository or global options


SYNOPSIS
--------
[verse]
'git config' [<file-option>] [--type=<type>] [--fixed-value] [--show-origin] [--show-scope] [-z|--null] <name> [<value> [<value-pattern>]]
'git config' [<file-option>] [--type=<type>] --add <name> <value>
'git config' [<file-option>] [--type=<type>] [--fixed-value] --replace-all <name> <value> [<value-pattern>]
'git config' [<file-option>] [--type=<type>] [--show-origin] [--show-scope] [-z|--null] [--fixed-value] --get <name> [<value-pattern>]
'git config' [<file-option>] [--type=<type>] [--show-origin] [--show-scope] [-z|--null] [--fixed-value] --get-all <name> [<value-pattern>]
'git config' [<file-option>] [--type=<type>] [--show-origin] [--show-scope] [-z|--null] [--fixed-value] [--name-only] --get-regexp <name-regex> [<value-pattern>]
'git config' [<file-option>] [--type=<type>] [-z|--null] --get-urlmatch <name> <URL>
'git config' [<file-option>] [--fixed-value] --unset <name> [<value-pattern>]
'git config' [<file-option>] [--fixed-value] --unset-all <name> [<value-pattern>]
'git config' [<file-option>] --rename-section <old-name> <new-name>
'git config' [<file-option>] --remove-section <name>
'git config' [<file-option>] [--show-origin] [--show-scope] [-z|--null] [--name-only] -l | --list
'git config' [<file-option>] --get-color <name> [<default>]
'git config' [<file-option>] --get-colorbool <name> [<stdout-is-tty>]
'git config' [<file-option>] -e | --edit

DESCRIPTION
-----------
You can query/set/replace/unset options with this command. The name is
actually the section and the key separated by a dot, and the value will be
escaped.

Multiple lines can be added to an option by using the `--add` option.
If you want to update or unset an option which can occur on multiple
lines, a `value-pattern` (which is an extended regular expression,
unless the `--fixed-value` option is given) needs to be given.  Only the
existing values that match the pattern are updated or unset.  If
you want to handle the lines that do *not* match the pattern, just
prepend a single exclamation mark in front (see also <<EXAMPLES>>),
but note that this only works when the `--fixed-value` option is not
in use.

The `--type=<type>` option instructs 'git config' to ensure that incoming and
outgoing values are canonicalize-able under the given <type>.  If no
`--type=<type>` is given, no canonicalization will be performed. Callers may
unset an existing `--type` specifier with `--no-type`.

When reading, the values are read from the system, global and
repository local configuration files by default, and options
`--system`, `--global`, `--local`, `--worktree` and
`--file <filename>` can be used to tell the command to read from only
that location (see <<FILES>>).

When writing, the new value is written to the repository local
configuration file by default, and options `--system`, `--global`,
`--worktree`, `--file <filename>` can be used to tell the command to
write to that location (you can say `--local` but that is the
default).

This command will fail with non-zero status upon error.  Some exit
codes are:

- The section or key is invalid (ret=1),
- no section or name was provided (ret=2),
- the config file is invalid (ret=3),
- the config file cannot be written (ret=4),
- you try to unset an option which does not exist (ret=5),
- you try to unset/set an option for which multiple lines match (ret=5), or
- you try to use an invalid regexp (ret=6).

On success, the command returns the exit code 0.

A list of all available configuration variables can be obtained using the
`git help --config` command.

[[OPTIONS]]
OPTIONS
-------

--replace-all::
        Default behavior is to replace at most one line. This replaces
        all lines matching the key (and optionally the `value-pattern`).

--add::
        Adds a new line to the option without altering any existing
        values.  This is the same as providing '^$' as the `value-pattern`
        in `--replace-all`.

--get::
        Get the value for a given key (optionally filtered by a regex
        matching the value). Returns error code 1 if the key was not
        found and the last value if multiple key values were found.

--get-all::
        Like get, but returns all values for a multi-valued key.

--get-regexp::
        Like --get-all, but interprets the name as a regular expression and
        writes out the key names.  Regular expression matching is currently
        case-sensitive and done against a canonicalized version of the key
        in which section and variable names are lowercased, but subsection
        names are not.

--get-urlmatch <name> <URL>::
        When given a two-part name section.key, the value for
        section.<URL>.key whose <URL> part matches the best to the
        given URL is returned (if no such key exists, the value for
        section.key is used as a fallback).  When given just the
        section as name, do so for all the keys in the section and
        list them.  Returns error code 1 if no value is found.

--global::
        For writing options: write to global `~/.gitconfig` file
        rather than the repository `.git/config`, write to
        `$XDG_CONFIG_HOME/git/config` file if this file exists and the
        `~/.gitconfig` file doesn't.
+
For reading options: read only from global `~/.gitconfig` and from
`$XDG_CONFIG_HOME/git/config` rather than from all available files.
+
See also <<FILES>>.

--system::
        For writing options: write to system-wide
        `$(prefix)/etc/gitconfig` rather than the repository
        `.git/config`.
+
For reading options: read only from system-wide `$(prefix)/etc/gitconfig`
rather than from all available files.
+
See also <<FILES>>.

--local::
        For writing options: write to the repository `.git/config` file.
        This is the default behavior.
+
For reading options: read only from the repository `.git/config` rather than
from all available files.
+
See also <<FILES>>.

--worktree::
        Similar to `--local` except that `.git/config.worktree` is
        read from or written to if `extensions.worktreeConfig` is
        present. If not it's the same as `--local`.

-f <config-file>::
--file <config-file>::
        For writing options: write to the specified file rather than the
        repository `.git/config`.
+
For reading options: read only from the specified file rather than from all
available files.
+
See also <<FILES>>.

--blob <blob>::
        Similar to `--file` but use the given blob instead of a file. E.g.
        you can use 'master:.gitmodules' to read values from the file
        '.gitmodules' in the master branch. See "SPECIFYING REVISIONS"
        section in linkgit:gitrevisions[7] for a more complete list of
        ways to spell blob names.

--remove-section::
        Remove the given section from the configuration file.

--rename-section::
        Rename the given section to a new name.

--unset::
        Remove the line matching the key from config file.

--unset-all::
        Remove all lines matching the key from config file.

-l::
--list::
        List all variables set in config file, along with their values.

--fixed-value::
        When used with the `value-pattern` argument, treat `value-pattern` as
        an exact string instead of a regular expression. This will restrict
        the name/value pairs that are matched to only those where the value
        is exactly equal to the `value-pattern`.

--type <type>::
  'git config' will ensure that any input or output is valid under the given
  type constraint(s), and will canonicalize outgoing values in `<type>`'s
  canonical form.
+
Valid `<type>`'s include:
+
- 'bool': canonicalize values as either "true" or "false".
- 'int': canonicalize values as simple decimal numbers. An optional suffix of
  'k', 'm', or 'g' will cause the value to be multiplied by 1024, 1048576, or
  1073741824 upon input.
- 'bool-or-int': canonicalize according to either 'bool' or 'int', as described
  above.
- 'path': canonicalize by adding a leading `~` to the value of `$HOME` and
  `~user` to the home directory for the specified user. This specifier has no
  effect when setting the value (but you can use `git config section.variable
  ~/` from the command line to let your shell do the expansion.)
- 'expiry-date': canonicalize by converting from a fixed or relative date-string
  to a timestamp. This specifier has no effect when setting the value.
- 'color': When getting a value, canonicalize by converting to an ANSI color
  escape sequence. When setting a value, a sanity-check is performed to ensure
  that the given value is canonicalize-able as an ANSI color, but it is written
  as-is.
+

--bool::
--int::
--bool-or-int::
--path::
--expiry-date::
  Historical options for selecting a type specifier. Prefer instead `--type`
  (see above).

--no-type::
  Un-sets the previously set type specifier (if one was previously set). This
  option requests that 'git config' not canonicalize the retrieved variable.
  `--no-type` has no effect without `--type=<type>` or `--<type>`.

-z::
--null::
        For all options that output values and/or keys, always
        end values with the null character (instead of a
        newline). Use newline instead as a delimiter between
        key and value. This allows for secure parsing of the
        output without getting confused e.g. by values that
        contain line breaks.

--name-only::
        Output only the names of config variables for `--list` or
        `--get-regexp`.

--show-origin::
        Augment the output of all queried config options with the
        origin type (file, standard input, blob, command line) and
        the actual origin (config file path, ref, or blob id if
        applicable).

--show-scope::
        Similar to `--show-origin` in that it augments the output of
        all queried config options with the scope of that value
        (local, global, system, command).

--get-colorbool <name> [<stdout-is-tty>]::

        Find the color setting for `<name>` (e.g. `color.diff`) and output
        "true" or "false".  `<stdout-is-tty>` should be either "true" or
        "false", and is taken into account when configuration says
        "auto".  If `<stdout-is-tty>` is missing, then checks the standard
        output of the command itself, and exits with status 0 if color
        is to be used, or exits with status 1 otherwise.
        When the color setting for `name` is undefined, the command uses
        `color.ui` as fallback.

--get-color <name> [<default>]::

        Find the color configured for `name` (e.g. `color.diff.new`) and
        output it as the ANSI color escape sequence to the standard
        output.  The optional `default` parameter is used instead, if
        there is no color configured for `name`.
+
`--type=color [--default=<default>]` is preferred over `--get-color`
(but note that `--get-color` will omit the trailing newline printed by
`--type=color`).

-e::
--edit::
        Opens an editor to modify the specified config file; either
        `--system`, `--global`, or repository (default).

--[no-]includes::
        Respect `include.*` directives in config files when looking up
        values. Defaults to `off` when a specific file is given (e.g.,
        using `--file`, `--global`, etc) and `on` when searching all
        config files.

--default <value>::
  When using `--get`, and the requested variable is not found, behave as if
  <value> were the value assigned to the that variable.

CONFIGURATION
-------------
`pager.config` is only respected when listing configuration, i.e., when
using `--list` or any of the `--get-*` which may return multiple results.
The default is to use a pager.

[[FILES]]
FILES
-----

If not set explicitly with `--file`, there are four files where
'git config' will search for configuration options:

$(prefix)/etc/gitconfig::
        System-wide configuration file.

$XDG_CONFIG_HOME/git/config::
        Second user-specific configuration file. If $XDG_CONFIG_HOME is not set
        or empty, `$HOME/.config/git/config` will be used. Any single-valued
        variable set in this file will be overwritten by whatever is in
        `~/.gitconfig`.  It is a good idea not to create this file if
        you sometimes use older versions of Git, as support for this
        file was added fairly recently.

~/.gitconfig::
        User-specific configuration file. Also called "global"
        configuration file.

$GIT_DIR/config::
        Repository specific configuration file.

$GIT_DIR/config.worktree::
        This is optional and is only searched when
        `extensions.worktreeConfig` is present in $GIT_DIR/config.

If no further options are given, all reading options will read all of these
files that are available. If the global or the system-wide configuration
file are not available they will be ignored. If the repository configuration
file is not available or readable, 'git config' will exit with a non-zero
error code. However, in neither case will an error message be issued.

The files are read in the order given above, with last value found taking
precedence over values read earlier.  When multiple values are taken then all
values of a key from all files will be used.

You may override individual configuration parameters when running any git
command by using the `-c` option. See linkgit:git[1] for details.

All writing options will per default write to the repository specific
configuration file. Note that this also affects options like `--replace-all`
and `--unset`. *'git config' will only ever change one file at a time*.

You can override these rules using the `--global`, `--system`,
`--local`, `--worktree`, and `--file` command-line options; see
<<OPTIONS>> above.


ENVIRONMENT
-----------

GIT_CONFIG_GLOBAL::
GIT_CONFIG_SYSTEM::
        Take the configuration from the given files instead from global or
        system-level configuration. See linkgit:git[1] for details.

GIT_CONFIG_NOSYSTEM::
        Whether to skip reading settings from the system-wide
        $(prefix)/etc/gitconfig file. See linkgit:git[1] for details.

See also <<FILES>>.

GIT_CONFIG_COUNT::
GIT_CONFIG_KEY_<n>::
GIT_CONFIG_VALUE_<n>::
        If GIT_CONFIG_COUNT is set to a positive number, all environment pairs
        GIT_CONFIG_KEY_<n> and GIT_CONFIG_VALUE_<n> up to that number will be
        added to the process's runtime configuration. The config pairs are
        zero-indexed. Any missing key or value is treated as an error. An empty
        GIT_CONFIG_COUNT is treated the same as GIT_CONFIG_COUNT=0, namely no
        pairs are processed. These environment variables will override values
        in configuration files, but will be overridden by any explicit options
        passed via `git -c`.
+
This is useful for cases where you want to spawn multiple git commands
with a common configuration but cannot depend on a configuration file,
for example when writing scripts.

GIT_CONFIG::
        If no `--file` option is provided to `git config`, use the file
        given by `GIT_CONFIG` as if it were provided via `--file`. This
        variable has no effect on other Git commands, and is mostly for
        historical compatibility; there is generally no reason to use it
        instead of the `--file` option.

[[EXAMPLES]]
EXAMPLES
--------

Given a .git/config like this:

------------
#
# This is the config file, and
# a '#' or ';' character indicates
# a comment
#

; core variables
[core]
        ; Don't trust file modes
        filemode = false

; Our diff algorithm
[diff]
        external = /usr/local/bin/diff-wrapper
        renames = true

; Proxy settings
[core]
        gitproxy=proxy-command for kernel.org
        gitproxy=default-proxy ; for all the rest

; HTTP
[http]
        sslVerify
[http "https://weak.example.com"]
        sslVerify = false
        cookieFile = /tmp/cookie.txt
------------

you can set the filemode to true with

------------
% git config core.filemode true
------------

The hypothetical proxy command entries actually have a postfix to discern
what URL they apply to. Here is how to change the entry for kernel.org
to "ssh".

------------
% git config core.gitproxy '"ssh" for kernel.org' 'for kernel.org$'
------------

This makes sure that only the key/value pair for kernel.org is replaced.

To delete the entry for renames, do

------------
% git config --unset diff.renames
------------

If you want to delete an entry for a multivar (like core.gitproxy above),
you have to provide a regex matching the value of exactly one line.

To query the value for a given key, do

------------
% git config --get core.filemode
------------

or

------------
% git config core.filemode
------------

or, to query a multivar:

------------
% git config --get core.gitproxy "for kernel.org$"
------------

If you want to know all the values for a multivar, do:

------------
% git config --get-all core.gitproxy
------------

If you like to live dangerously, you can replace *all* core.gitproxy by a
new one with

------------
% git config --replace-all core.gitproxy ssh
------------

However, if you really only want to replace the line for the default proxy,
i.e. the one without a "for ..." postfix, do something like this:

------------
% git config core.gitproxy ssh '! for '
------------

To actually match only values with an exclamation mark, you have to

------------
% git config section.key value '[!]'
------------

To add a new proxy, without altering any of the existing ones, use

------------
% git config --add core.gitproxy '"proxy-command" for example.com'
------------

An example to use customized color from the configuration in your
script:

------------
#!/bin/sh
WS=$(git config --get-color color.diff.whitespace "blue reverse")
RESET=$(git config --get-color "" "reset")
echo "${WS}your whitespace color or blue reverse${RESET}"
------------

For URLs in `https://weak.example.com`, `http.sslVerify` is set to
false, while it is set to `true` for all others:

------------
% git config --type=bool --get-urlmatch http.sslverify https://good.example.com
true
% git config --type=bool --get-urlmatch http.sslverify https://weak.example.com
false
% git config --get-urlmatch http https://weak.example.com
http.cookieFile /tmp/cookie.txt
http.sslverify false
------------

include::config.txt[]

BUGS
----
When using the deprecated `[section.subsection]` syntax, changing a value
will result in adding a multi-line key instead of a change, if the subsection
is given with at least one uppercase character. For example when the config
looks like

--------
  [section.subsection]
    key = value1
--------

and running `git config section.Subsection.key value2` will result in

--------
  [section.subsection]
    key = value1
    key = value2
--------


GIT
---
Part of the linkgit:git[1] suite