[apple/libc.git] / stdlib / FreeBSD / getsubopt.3

.\" Copyright (c) 1990, 1991, 1993
.\"	The Regents of the University of California.  All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 4. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\"     @(#)getsubopt.3	8.1 (Berkeley) 6/9/93
.\" $FreeBSD: src/lib/libc/stdlib/getsubopt.3,v 1.11 2007/01/09 00:28:10 imp Exp $
.\"
.Dd June 9, 1993
.Dt GETSUBOPT 3
.Os
.Sh NAME
.Nm getsubopt
.Nd get sub options from an argument
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In stdlib.h
.Vt extern char *suboptarg ;
.Ft int
.Fo getsubopt
.Fa "char **optionp"
.Fa "char *const *keylistp"
.Fa "char **valuep"
.Fc
.Sh DESCRIPTION
The
.Fn getsubopt
function
parses a string containing tokens that are delimited
by one or more tab, space, or comma
.Pq Ql \&,
characters.
It is intended for use in parsing groups of option arguments
that are provided as part of a utility command line.
.Pp
The argument
.Fa optionp
is a pointer to a pointer to the string.
The argument
.Fa keylistp
is a pointer to a
.Dv NULL Ns -terminated
array of pointers to strings.
.Pp
The
.Fn getsubopt
function
returns the zero-based offset of the pointer in the
.Fa keylistp
array, referencing a string which matches the first token in the string
 or \-1 if the string contains no tokens or
.Fa keylistp
does not contain a matching string.
.Pp
If the token is of the form ``name=value'', the location referenced by
.Fa valuep
will be set to point to the start of the ``value'' portion of the token.
.Pp
On return from
.Fn getsubopt ,
.Fa optionp
will be set to point to the start of the next token in the string,
or the null at the end of the string if no more tokens are present.
The external variable
.Fa suboptarg
will be set to point to the start of the current token, or
.Dv NULL
if no
tokens were present.
The argument
.Fa valuep
will be set to point to the ``value'' portion of the token, or
.Dv NULL
if no ``value'' portion was present.
.Sh EXAMPLES
.Bd -literal -compact
char *keylistp[] = {
	#define	ONE	0
		"one",
	#define	TWO	1
		"two",
	NULL
};

\&...

extern char *optarg, *suboptarg;
char *options, *value;

while ((ch = getopt(argc, argv, "ab:")) != \-1) {
	switch(ch) {
	case 'a':
		/* process ``a'' option */
		break;
	case 'b':
		options = optarg;
		while (*options) {
			switch(getsubopt(&options, keylistp, &value)) {
			case ONE:
				/* process ``one'' sub option */
				break;
			case TWO:
				/* process ``two'' sub option */
				if (!value)
					error("no value for two");
				i = atoi(value);
				break;
			case \-1:
				if (suboptarg)
					error("illegal sub option %s",
					  suboptarg);
				else
					error("missing sub option");
				break;
		}
		break;
	}
.Ed
.Sh SEE ALSO
.Xr getopt 3 ,
.Xr strsep 3
.Sh HISTORY
The
.Fn getsubopt
function first appeared in
.Bx 4.4 .
Commit	Line	Data
5b2abdfb A	1	.\" Copyright (c) 1990, 1991, 1993
	2	.\" The Regents of the University of California. All rights reserved.
	3	.\"
	4	.\" Redistribution and use in source and binary forms, with or without
	5	.\" modification, are permitted provided that the following conditions
	6	.\" are met:
	7	.\" 1. Redistributions of source code must retain the above copyright
	8	.\" notice, this list of conditions and the following disclaimer.
	9	.\" 2. Redistributions in binary form must reproduce the above copyright
	10	.\" notice, this list of conditions and the following disclaimer in the
	11	.\" documentation and/or other materials provided with the distribution.
5b2abdfb A	12	.\" 4. Neither the name of the University nor the names of its contributors
	13	.\" may be used to endorse or promote products derived from this software
	14	.\" without specific prior written permission.
	15	.\"
	16	.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	17	.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	18	.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	19	.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	20	.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	21	.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	22	.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	23	.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	24	.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	25	.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	26	.\" SUCH DAMAGE.
	27	.\"
	28	.\" @(#)getsubopt.3 8.1 (Berkeley) 6/9/93
1f2f436a	29	.\" $FreeBSD: src/lib/libc/stdlib/getsubopt.3,v 1.11 2007/01/09 00:28:10 imp Exp $
5b2abdfb A	30	.\"
	31	.Dd June 9, 1993
	32	.Dt GETSUBOPT 3
	33	.Os
	34	.Sh NAME
	35	.Nm getsubopt
	36	.Nd get sub options from an argument
	37	.Sh LIBRARY
	38	.Lb libc
	39	.Sh SYNOPSIS
3d9156a7	40	.In stdlib.h
5b2abdfb A	41	.Vt extern char *suboptarg ;
5b2abdfb A	42	.Ft int
ad3c9f2a A	43	.Fo getsubopt
	44	.Fa "char **optionp"
	45	.Fa "char const keylistp"
	46	.Fa "char **valuep"
	47	.Fc
5b2abdfb A	48	.Sh DESCRIPTION
	49	The
	50	.Fn getsubopt
	51	function
ad3c9f2a A	52	parses a string containing tokens that are delimited
ad3c9f2a A	53	by one or more tab, space, or comma
5b2abdfb A	54	.Pq Ql \&,
5b2abdfb A	55	characters.
ad3c9f2a A	56	It is intended for use in parsing groups of option arguments
ad3c9f2a A	57	that are provided as part of a utility command line.
5b2abdfb A	58	.Pp
	59	The argument
	60	.Fa optionp
	61	is a pointer to a pointer to the string.
	62	The argument
ad3c9f2a	63	.Fa keylistp
5b2abdfb A	64	is a pointer to a
	65	.Dv NULL Ns -terminated
	66	array of pointers to strings.
	67	.Pp
	68	The
	69	.Fn getsubopt
	70	function
	71	returns the zero-based offset of the pointer in the
ad3c9f2a A	72	.Fa keylistp
	73	array, referencing a string which matches the first token in the string
	74	or \-1 if the string contains no tokens or
	75	.Fa keylistp
5b2abdfb A	76	does not contain a matching string.
	77	.Pp
	78	If the token is of the form ``name=value'', the location referenced by
	79	.Fa valuep
	80	will be set to point to the start of the ``value'' portion of the token.
	81	.Pp
	82	On return from
	83	.Fn getsubopt ,
	84	.Fa optionp
	85	will be set to point to the start of the next token in the string,
	86	or the null at the end of the string if no more tokens are present.
	87	The external variable
	88	.Fa suboptarg
	89	will be set to point to the start of the current token, or
	90	.Dv NULL
	91	if no
	92	tokens were present.
	93	The argument
	94	.Fa valuep
	95	will be set to point to the ``value'' portion of the token, or
	96	.Dv NULL
	97	if no ``value'' portion was present.
	98	.Sh EXAMPLES
	99	.Bd -literal -compact
ad3c9f2a	100	char *keylistp[] = {
5b2abdfb A	101	#define ONE 0
	102	"one",
	103	#define TWO 1
	104	"two",
	105	NULL
	106	};
	107
	108	\&...
	109
	110	extern char optarg, suboptarg;
	111	char options, value;
	112
	113	while ((ch = getopt(argc, argv, "ab:")) != \-1) {
	114	switch(ch) {
	115	case 'a':
	116	/* process ``a'' option */
	117	break;
	118	case 'b':
	119	options = optarg;
	120	while (*options) {
ad3c9f2a	121	switch(getsubopt(&options, keylistp, &value)) {
5b2abdfb A	122	case ONE:
	123	/* process ``one'' sub option */
	124	break;
	125	case TWO:
	126	/* process ``two'' sub option */
	127	if (!value)
	128	error("no value for two");
	129	i = atoi(value);
	130	break;
	131	case \-1:
	132	if (suboptarg)
	133	error("illegal sub option %s",
	134	suboptarg);
	135	else
	136	error("missing sub option");
	137	break;
	138	}
	139	break;
	140	}
	141	.Ed
	142	.Sh SEE ALSO
	143	.Xr getopt 3 ,
	144	.Xr strsep 3
	145	.Sh HISTORY
	146	The
	147	.Fn getsubopt
	148	function first appeared in
	149	.Bx 4.4 .