strstr(3)

NAME

strstr, strcasestr — locate a substring in a string

SYNOPSIS

#include <string.h>

char *
strstr(const char *big, const char *little);

char *
strcasestr(const char *big, const char *little);

DESCRIPTION

The strstr() function locates the first occurrence of the NUL-terminated string little in the NUL-terminated string big.

The strcasestr() function is similar to strstr() but ignores the case of both strings.

RETURN VALUES

If little is an empty string, big is returned; if little occurs nowhere in big, NULL is returned; otherwise a pointer to the first character of the first occurrence of little is returned.

SEE ALSO

memchr(3), memmem(3), strchr(3), strcspn(3), strpbrk(3), strrchr(3), strsep(3), strspn(3), strtok(3), wcsstr(3)

STANDARDS

The strstr() function conforms to ANSI X3.159-1989 (“ANSI C89”).

HISTORY

The strstr() function first appeared in 4.3BSD-Reno. The strcasestr() function appeared in glibc 2.1, was reimplemented for FreeBSD 4.5 and ported to OpenBSD 3.8.