GETSUBOPT(3) BSD Programmer's Manual GETSUBOPT(3)
getsubopt - get sub options from an argument
#include <stdlib.h>
extern char *suboptarg;
int
getsubopt(char **optionp, char * const *tokens, char **valuep);
The 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 com-
mand line.
The argument optionp is a pointer to a pointer to the string. The argu-
ment 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 NUL 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("illegal sub option %s",
suboptarg);
else
error("missing sub option");
break;
}
break;
}
getopt(3), strsep(3)
The getsubopt() function first appeared in 4.4BSD.
MirBSD #10-current June 9, 1993 1