getsubopt - Parse suboption arguments from a command line
#include <stdlib.h>
int getsubopt(
char **optionp,
char *tokens[],
char **valuep );
Standard C Library (libc)
Interfaces documented on this reference page conform to
industry standards as follows:
getsubopt(): XPG4-UNIX
Refer to the standards(5) reference page for more information
about industry standards and associated tags.
Specifies the address of a pointer to the option string.
Specifies an array of possible suboption tokens. Specifies
the address of a value string pointer.
The getsubopt() function parses suboption arguments in a
option argument that was initially parsed by the getopt()
function. These suboption arguments must be separated by
commas and may consist of either a single token, or a
token-value pair separated by an equal sign. Because commas
delimit suboption arguments in the option string, commas
are not allowed to be part of the suboption arguments
or the value of a suboption argument. Similarly, because
the equal sign separates a token from its value, a token
must not contain an equal sign.
The following command line for the mount command gives an
example of this syntax: mount -o ro,nosuid,rsize=8192
paradox:/u2 /u2
In this example, the suboption consists of three arguments:
ro and nosuid (tokens), and rsize=8192 (a tokenvalue
pair).
When a suboption argument is found in the *optionp string
that matches a string in the token array, the index of the
matching string in the array is returned. If no match is
found, then a -1 is returned. After each match, the
*optionp string is updated to point past the matched suboption
argument to the next suboption argument in the
list. If the suboption argument matched is the last in the
string, *optionp is set to the null pointer. If the suboption
argument matched is a token-value pair, then *valuep
is set to point to the value. If there is no value,
then *valuep is to the null pointer.
The token array is a list of pointers to strings. The end
of the array is signified by a NULL pointer.
Upon successful completion, the getsubopt() function
returns the index of the token or suboption argument that
matches the suboption argument in the input string. Otherwise,
if no match is found, it returns a value of -1.
No errors are defined for this routine.
Functions: getopt(3)
Standards: standards(5)
getsubopt(3)
[ Back ] | 