NAME
strsep —
separate strings
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include
<string.h>
char *
strsep(char
**stringp, const 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., a character in the string
delim occurs as the first character of
*stringp) can be detected by comparing the location
referenced by the returned pointer to
‘\0’.
If *stringp is initially
NULL,
strsep()
returns NULL.
EXAMPLES
The following uses strsep() to parse a
string, and prints each token in separate line:
char *token, *string, *tofree;
tofree = string = strdup("abc,def,ghi");
assert(string != NULL);
while ((token = strsep(&string, ",")) != NULL)
printf("%s\n", token);
free(tofree);
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') if (++ap >= &argv[10]) break;
SEE ALSO
memchr(3), strchr(3), strcspn(3), strpbrk(3), strrchr(3), strspn(3), strstr(3), strtok(3)
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 ISO/IEC 9899:1990
(“ISO C90”)) 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.