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getsubopt(3)
NAME
  getsubopt - 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 standards
  as follows:

  getsubopt():	XPG4-UNIX

  Refer to the standards(5) reference page for more information about
  industry standards and associated tags.

PARAMETERS
  optionp
      Specifies the address of a pointer to the option string.

  tokens[ ]
      Specifies an array of possible suboption tokens.

  valuep
      Specifies the address of a value string pointer.

DESCRIPTION
  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 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)

Index for Section 3

Alphabetical listing for G

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