/usr/bin/getopt
getopt - コマンドオプションを解析する（機能強化）
SYNOPSIS
getopt optstring parameters
getopt [options] [--] optstring parameters
getopt [options] -o|--options optstring [options] [--] parameters
DESCRIPTION
getoptは、コマンドラインのオプションを分割（パース）して、シェル手続きで簡単にパースできるようにしたり、有効なオプションかどうかをチェックしたりするのに使われる。 そのためにGNU getopt(3)ルーチンを使用する。
getopt が呼び出されるパラメータは 2 つの部分に分けられる。 getopt がパースする方法を変更するオプション (SYNOPSIS 内のオプションと optstring) と、パースされるパラメータ (SYNOPSIS 内のパラメータ) である。 2番目の部分は、オプション引数ではない最初のパラメータ、 または '--' が最初に出現した後のパラメータから始まる。 最初の部分で'-o'または'--options'オプションが見つからない場合、 2番目の部分の最初のパラメーターが短いオプション文字列として使われる。
環境変数 GETOPT_COMPATIBLE が設定されている場合、 または最初のパラメータがオプションでない場合 (SYNOPSIS の最初の書式である '-' で始まらない場合)、 getopt は他のバージョンの getopt(1) と互換性のある出力を生成する。 パラメータシャッフルを行い、オプション引数を認識する (詳細については COMPATIBILITY を参照のこと)。
従来の getopt(1) の実装は、引数やオプション以外のパラメータに含まれる空白文字やその他の (シェル固有の) 特殊文字に対処できない。 この問題を解決するために、この実装では引用符で囲まれた出力を生成することができる。 これはこれらの文字を保持する効果があるが、他のバージョンと互換性のない方法（SYNOPSISの2番目か3番目の形式）でgetoptを呼び出さなければならない。 この拡張バージョンの getopt(1) がインストールされているかどうかを調べるには、特別なテストオプション (-T) を使用する。
OPTIONS
-a, --alternative
Allow long options to start with a single '-'.
-h, --help
Display help text and exit. No other output is generated.
-l, --longoptions longopts
The long (multi-character) options to be recognized. More than one option name may be speci‐
fied at once, by separating the names with commas. This option may be given more than once,
the longopts are cumulative. Each long option name in longopts may be followed by one colon
to indicate it has a required argument, and by two colons to indicate it has an optional ar‐
gument.
-n, --name progname
The name that will be used by the getopt(3) routines when it reports errors. Note that er‐
rors of getopt(1) are still reported as coming from getopt.
-o, --options shortopts
The short (one-character) options to be recognized. If this option is not found, the first
parameter of getopt that does not start with a '-' (and is not an option argument) is used as
the short options string. Each short option character in shortopts may be followed by one
colon to indicate it has a required argument, and by two colons to indicate it has an op‐
tional argument. The first character of shortopts may be '+' or '-' to influence the way op‐
tions are parsed and output is generated (see section SCANNING MODES for details).
-q, --quiet
Disable error reporting by getopt(3).
-Q, --quiet-output
Do not generate normal output. Errors are still reported by getopt(3), unless you also use
-q.
-s, --shell shell
Set quoting conventions to those of shell. If the -s option is not given, the BASH conven‐
tions are used. Valid arguments are currently 'sh' 'bash', 'csh', and 'tcsh'.
-T, --test
Test if your getopt(1) is this enhanced version or an old version. This generates no output,
and sets the error status to 4. Other implementations of getopt(1), and this version if the
environment variable GETOPT_COMPATIBLE is set, will return '--' and error status 0.
-u, --unquoted
Do not quote the output. Note that whitespace and special (shell-dependent) characters can
cause havoc in this mode (like they do with other getopt(1) implementations).
-V, --version
Display version information and exit. No other output is generated.
PARSING
This section specifies the format of the second part of the parameters of getopt (the parameters in
the SYNOPSIS). The next section (OUTPUT) describes the output that is generated. These parameters
were typically the parameters a shell function was called with. Care must be taken that each param‐
eter the shell function was called with corresponds to exactly one parameter in the parameter list
of getopt (see the EXAMPLES). All parsing is done by the GNU getopt(3) routines.
The parameters are parsed from left to right. Each parameter is classified as a short option, a
long option, an argument to an option, or a non-option parameter.
A simple short option is a '-' followed by a short option character. If the option has a required
argument, it may be written directly after the option character or as the next parameter (i.e., sep‐
arated by whitespace on the command line). If the option has an optional argument, it must be writ‐
ten directly after the option character if present.
It is possible to specify several short options after one '-', as long as all (except possibly the
last) do not have required or optional arguments.
A long option normally begins with '--' followed by the long option name. If the option has a re‐
quired argument, it may be written directly after the long option name, separated by '=', or as the
next argument (i.e., separated by whitespace on the command line). If the option has an optional
argument, it must be written directly after the long option name, separated by '=', if present (if
you add the '=' but nothing behind it, it is interpreted as if no argument was present; this is a
slight bug, see the BUGS). Long options may be abbreviated, as long as the abbreviation is not am‐
biguous.
Each parameter not starting with a '-', and not a required argument of a previous option, is a
non-option parameter. Each parameter after a '--' parameter is always interpreted as a non-option
parameter. If the environment variable POSIXLY_CORRECT is set, or if the short option string
started with a '+', all remaining parameters are interpreted as non-option parameters as soon as the
first non-option parameter is found.
OUTPUT
Output is generated for each element described in the previous section. Output is done in the same
order as the elements are specified in the input, except for non-option parameters. Output can be
done in compatible (unquoted) mode, or in such way that whitespace and other special characters
within arguments and non-option parameters are preserved (see QUOTING). When the output is pro‐
cessed in the shell script, it will seem to be composed of distinct elements that can be processed
one by one (by using the shift command in most shell languages). This is imperfect in unquoted
mode, as elements can be split at unexpected places if they contain whitespace or special charac‐
ters.
If there are problems parsing the parameters, for example because a required argument is not found
or an option is not recognized, an error will be reported on stderr, there will be no output for the
offending element, and a non-zero error status is returned.
For a short option, a single '-' and the option character are generated as one parameter. If the
option has an argument, the next parameter will be the argument. If the option takes an optional
argument, but none was found, the next parameter will be generated but be empty in quoting mode, but
no second parameter will be generated in unquoted (compatible) mode. Note that many other getopt(1)
implementations do not support optional arguments.
If several short options were specified after a single '-', each will be present in the output as a
separate parameter.
For a long option, '--' and the full option name are generated as one parameter. This is done re‐
gardless whether the option was abbreviated or specified with a single '-' in the input. Arguments
are handled as with short options.
Normally, no non-option parameters output is generated until all options and their arguments have
been generated. Then '--' is generated as a single parameter, and after it the non-option parame‐
ters in the order they were found, each as a separate parameter. Only if the first character of the
short options string was a '-', non-option parameter output is generated at the place they are found
in the input (this is not supported if the first format of the SYNOPSIS is used; in that case all
preceding occurrences of '-' and '+' are ignored).
QUOTING
In compatible mode, whitespace or 'special' characters in arguments or non-option parameters are not
handled correctly. As the output is fed to the shell script, the script does not know how it is
supposed to break the output into separate parameters. To circumvent this problem, this implementa‐
tion offers quoting. The idea is that output is generated with quotes around each parameter. When
this output is once again fed to the shell (usually by a shell eval command), it is split correctly
into separate parameters.
Quoting is not enabled if the environment variable GETOPT_COMPATIBLE is set, if the first form of
the SYNOPSIS is used, or if the option '-u' is found.
Different shells use different quoting conventions. You can use the '-s' option to select the shell
you are using. The following shells are currently supported: 'sh', 'bash', 'csh' and 'tcsh'. Actu‐
ally, only two 'flavors' are distinguished: sh-like quoting conventions and csh-like quoting conven‐
tions. Chances are that if you use another shell script language, one of these flavors can still be
used.
SCANNING MODES
The first character of the short options string may be a '-' or a '+' to indicate a special scanning
mode. If the first calling form in the SYNOPSIS is used they are ignored; the environment variable
POSIXLY_CORRECT is still examined, though.
If the first character is '+', or if the environment variable POSIXLY_CORRECT is set, parsing stops
as soon as the first non-option parameter (i.e., a parameter that does not start with a '-') is
found that is not an option argument. The remaining parameters are all interpreted as non-option
parameters.
If the first character is a '-', non-option parameters are outputted at the place where they are
found; in normal operation, they are all collected at the end of output after a '--' parameter has
been generated. Note that this '--' parameter is still generated, but it will always be the last
parameter in this mode.
COMPATIBILITY
This version of getopt(1) is written to be as compatible as possible to other versions. Usually you
can just replace them with this version without any modifications, and with some advantages.
If the first character of the first parameter of getopt is not a '-', getopt goes into compatibility
mode. It will interpret its first parameter as the string of short options, and all other arguments
will be parsed. It will still do parameter shuffling (i.e., all non-option parameters are output at
the end), unless the environment variable POSIXLY_CORRECT is set.
The environment variable GETOPT_COMPATIBLE forces getopt into compatibility mode. Setting both this
environment variable and POSIXLY_CORRECT offers 100% compatibility for 'difficult' programs. Usu‐
ally, though, neither is needed.
In compatibility mode, leading '-' and '+' characters in the short options string are ignored.
RETURN CODES
getopt returns error code 0 for successful parsing, 1 if getopt(3) returns errors, 2 if it does not
understand its own parameters, 3 if an internal error occurs like out-of-memory, and 4 if it is
called with -T.
EXAMPLES
Example scripts for (ba)sh and (t)csh are provided with the getopt(1) distribution, and are in‐
stalled in /usr/share/doc/util-linux/getopt/ directory.
ENVIRONMENT
POSIXLY_CORRECT
This environment variable is examined by the getopt(3) routines. If it is set, parsing stops
as soon as a parameter is found that is not an option or an option argument. All remaining
parameters are also interpreted as non-option parameters, regardless whether they start with
a '-'.
GETOPT_COMPATIBLE
Forces getopt to use the first calling format as specified in the SYNOPSIS.
BUGS
getopt(3) can parse long options with optional arguments that are given an empty optional argument
(but cannot do this for short options). This getopt(1) treats optional arguments that are empty as
if they were not present.
The syntax if you do not want any short option variables at all is not very intuitive (you have to
set them explicitly to the empty string).
AUTHOR
Frodo Looijaard ⟨frodo@frodo.looijaard.name⟩
SEE ALSO
bash(1), tcsh(1), getopt(3)
AVAILABILITY
The getopt command is part of the util-linux package and is available from Linux Kernel Archive
⟨https://www.kernel.org/pub/linux/utils/util-linux/⟩.
External link
 | この記事は、Debianのmanpageの項目を翻訳一部改変しております。 |