NAME

strsep − separate strings

SYNOPSIS

#include <string.h> char ∗
strsep(stringp, delim)
char ∗∗stringp;
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. one caused by two adjacent delimiter characters, can be detected by comparing the location referenced by the pointer returned in ∗stringp to ‘\0’. 

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

EXAMPLES

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

char ∗∗ap, ∗argv[10], ∗inputstring;
 for (ap = argv; (∗ap = strsep(&inputstring, " \t")) != NULL;)
if (∗∗ap != ’\0’)
++ap;

HISTORY

The strsep() function is intended as a replacement for the strtok() function.  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 delimiter characters, or to be used for more than a single string at a time.  The strsep() function first appeared in 4.4BSD. 

4.4 Berkeley Distribution  —  January 12, 1996