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 ‘\0’ character) and replaces it with a ‘\0’. The loca‐
tion 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 ‘\0’.
If *stringp is initially NULL, strsep() returns NULL. The stresep()
function also takes an escape character that allows quoting the delimiter
character so that it can be part of the source string.
EXAMPLES
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 < &argv[9] &&
(*ap = strsep(&inputstring, " \t")) != NULL;) {
if (**ap != '\0')
ap++;
}
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 ANSI X3.159-1989 (“ANSI C89”)) 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 August 12, 2006 BSD
