STRSTR(3)						     Linux Programmer's Manual							 STRSTR(3)

NAME

       strstr, strcasestr - locate a substring

SYNOPSIS

       #include <string.h>

       char *strstr(const char *haystack, const char *needle);

       #define _GNU_SOURCE	   /* See feature_test_macros(7) */

       #include <string.h>

       char *strcasestr(const char *haystack, const char *needle);

DESCRIPTION

       The strstr() function finds the first occurrence of the substring needle in the string haystack.  The terminating null bytes ('') are not
       compared.

       The strcasestr() function is like strstr(), but ignores the case of both arguments.

RETURN VALUE

       These functions return a pointer to the beginning of the located substring, or NULL if the substring is not found.

ATTRIBUTES

       For an explanation of the terms used in this section, see attributes(7).

       +-------------+---------------+----------------+
       |Interface    | Attribute     | Value	      |
       +-------------+---------------+----------------+
       |strstr()     | Thread safety | MT-Safe	      |
       +-------------+---------------+----------------+
       |strcasestr() | Thread safety | MT-Safe locale |
       +-------------+---------------+----------------+
CONFORMING TO

       strstr(): POSIX.1-2001, POSIX.1-2008, C89, C99.

       The strcasestr() function is a nonstandard extension.

SEE ALSO

       index(3), memchr(3), memmem(3), rindex(3), strcasecmp(3), strchr(3), string(3), strpbrk(3), strsep(3), strspn(3), strtok(3), wcsstr(3)

COLOPHON

       This page is part of release 4.15 of the Linux man-pages project.  A description of the project, information about reporting bugs, and  the
       latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.

GNU
								    2017-09-15								 STRSTR(3)