| GETSUBOPT(3) | Library Functions Manual | GETSUBOPT(3) | 
getsubopt —
#include <stdlib.h>
extern char *suboptarg
int
  
  getsubopt(char
    **optionp, char * const
    *tokens, char
    **valuep);
getsubopt() function parses a string containing
  tokens delimited by one or more tab, space or comma
  (‘,’) characters. It is intended for use
  in parsing groups of option arguments provided as part of a utility command
  line.
The argument optionp is a pointer to a
    pointer to the string. The argument tokens is a
    pointer to a NULL-terminated array of pointers to
    strings.
The getsubopt() function returns the
    zero-based offset of the pointer in the tokens array
    referencing a string which matches the first token in the string, or -1 if
    the string contains no tokens or tokens does not
    contain a matching string.
If the token is of the form ``name=value'', the location referenced by valuep will be set to point to the start of the ``value'' portion of the token.
On return from getsubopt(),
    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 suboptarg will be
    set to point to the start of the current token, or
    NULL if no tokens were present. The argument
    valuep will be set to point to the ``value'' portion
    of the token, or NULL if no ``value'' portion was
    present.
char *tokens[] = {
	#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, tokens, &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("unknown sub option %s",
					  suboptarg);
				else
					error("missing sub option");
				break;
		}
		break;
	}
getsubopt() function first appeared in
  4.4BSD, and is included in IEEE Std
  1003.1-2008 (“POSIX.1”).
| August 15, 2018 | NetBSD 9.4 |