GETSUBOPT(3) MachTen Programmer’s Manual GETSUBOPT(3)
NAME
getsubopt - get sub options from an argument
SYNOPSIS
#include <stdlib.h>
extern char *suboptarg
int
getsubopt(char **optionp, char * const *tokens, char
**valuep)
DESCRIPTION
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 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 pre-
sent. The argument valuep will be set to point to the
‘‘value’’ portion
of the token, or NULL if no
‘‘value’’ portion was present.
EXAMPLE
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;
}
SEE ALSO
getopt(3), strsep(3)
HISTORY
The getsubopt() function first appeared in 4.4BSD.
4.4BSD June 9, 1993 2