getsubopt(3)getsubopt(3)NAMEgetsubopt - Parse suboption arguments from a command line
SYNOPSIS
#include <stdlib.h>
int getsubopt(
char **optionp,
char *tokens[],
char **valuep );
LIBRARY
Standard C Library (libc)
STANDARDS
Interfaces documented on this reference page conform to industry stan‐
dards as follows:
getsubopt(): XPG4-UNIX
Refer to the standards(5) reference page for more information about
industry standards and associated tags.
PARAMETERS
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.
DESCRIPTION
The getsubopt() function parses suboption arguments in a option argu‐
ment that was initially parsed by the getopt() function. These subop‐
tion 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 subop‐
tion 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 token-value 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.
RETURN VALUES
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.
ERRORS
No errors are defined for this routine.
SEE ALSO
Functions: getopt(3)
Standards: standards(5)getsubopt(3)
