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strsep(3)                BSD Library Functions Manual                strsep(3)


NAME

     strsep -- separate strings


LIBRARY

     Standard C Library (libc, -lc)


SYNOPSIS

     #include <string.h>

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


DESCRIPTION

     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., a character in the string delim occurs as the
     first character of *stringp) can be detected by comparing the location
     referenced by the returned pointer to `\0'.

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


EXAMPLES

     The following uses strsep() to parse a string, and prints each token in
     separate line:

           char *token, *string, *tofree;

           tofree = string = strdup("abc,def,ghi");
           assert(string != NULL);

           while ((token = strsep(&string, ",")) != NULL)
                   printf("%s\n", token);

           free(tofree);

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

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

           for (ap = argv; (*ap = strsep(&inputstring, " \t")) != NULL;)
                   if (**ap != '\0')
                           if (++ap >= &argv[10])
                                   break;


SEE ALSO

     memchr(3), strchr(3), strcspn(3), strpbrk(3), strrchr(3), strspn(3),
     strstr(3), strtok(3)


HISTORY

     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 ISO/IEC 9899:1990 (``ISO C90'')) 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.

BSD                            December 5, 2008                            BSD

Mac OS X 10.8 - Generated Fri Aug 31 05:59:55 CDT 2012