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STRSEP(3)                   BSD Programmer's Manual                  STRSEP(3)

     strsep - separate strings

     #include <&lt;string.h>&gt;

     char *
     strsep(char **stringp, char *delim);

     The strsep() function locates, in the string referenced by *stringp, the
     first occurrence of any character in the string delim (or the terminating
     `\0' character) and replaces it with a `\0'. The location of the next
     character after the delimiter character (or NULL, if the end of the
     string was reached) is stored in *stringp. The original value of *stringp
     is returned.

     An ``empty'' field, i.e. one caused by two adjacent delimiter characters,
     can be detected by comparing the location referenced by the pointer re-
     turned in *stringp to `\0'.

     If *stringp is initially NULL, strsep() returns NULL.

     The following uses strsep() to parse a string, containing tokens delimit-
     ed by white space, into an argument vector:

           char **ap, *argv[10], *inputstring;

           for (ap = argv; (*ap = strsep(&inputstring, " \t")) != NULL;)
                   if (**ap != '\0')

     The strsep() function is intended as a replacement for the strtok() func-
     tion.  While the strtok() function should be preferred for portability
     reasons (it conforms to ANSI C X3.159-1989 (``ANSI C '')) it is unable to
     handle empty fields, i.e. detect fields delimited by two adjacent delim-
     iter characters, or to be used for more than a single string at a time.
     The strsep() function first appeared in 4.4BSD.

4.4BSD                           June 9, 1993                                1