STRSEP(3) BSD Programmer's Manual STRSEP(3)
strsep - separate strings
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
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, *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