STRSEP(3) BSD Library Functions Manual STRSEP(3)
NAME
strsep, stresep -- separate strings
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <string.h>
char *
strsep(char **stringp, const char *delim);
char *
stresep(char **stringp, const char *delim, int escape);
DESCRIPTION
The strsep() function locates, in the nul-terminated string referenced by *stringp, the first occurrence of any character in the string delim
(or the terminating ' ' character) and replaces it with a ' '. 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 by strsep() to ' '.
If *stringp is initially NULL, strsep() returns NULL. The stresep() function also takes an escape character that allows quoting the delim-
iter character so that it can be part of the source string.
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 < &argv[9] &&
(*ap = strsep(&inputstring, " ")) != NULL;) {
if (**ap != ' ')
ap++;
}
HISTORY
The strsep() function is intended as a replacement for the strtok() function. While the strtok() function should be preferred for portabil-
ity reasons (it conforms to ANSI X3.159-1989 (``ANSI C89'')) it is unable to handle empty fields, i.e., detect fields delimited by two adja-
cent delimiter characters, or to be used for more than a single string at a time. The strsep() function first appeared in 4.4BSD.
BSD
August 12, 2006 BSD
