STRSTR

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 (‘\0’) 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

 

Multithreading (see pthreads(7))

The strstr() function is thread-safe.

The strcasestr() function is thread-safe with exceptions. It can be safely used in multithreaded applications, as long as setlocale(3) is not called to change the locale during its execution.  

CONFORMING TO

The strstr() function conforms to C89 and C99. The strcasestr() function is a nonstandard extension.

COLOPHON

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