strsep - separate strings
Standard C Library (libc, -lc)
strsep(char **stringp, const char *delim);
The strsep() function locates, in the null-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
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.
The following uses strsep() to parse a string, containing tokens delimited
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() function.
While the strtok() function should be preferred for portability
reasons (it conforms to ANSI 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.
BSD June 9, 1993 BSD
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