strstr(3) -- Linux man page

 

NAME

strstr - locate a substring  

SYNOPSIS

#include <string.h>

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

DESCRIPTION

The strstr() function finds the first occurrence of the substring needle in the string haystack. The terminating `\0' characters are not compared.  

RETURN VALUE

The strstr() function returns a pointer to the beginning of the substring, or NULL if the substring is not found.  

BUGS

Early versions of Linux libc (like 4.5.26) would not allow an empty argument. Later versions (like 4.6.27) work correctly, and return haystack when needle is empty.  

CONFORMING TO

ISO 9899  

SEE ALSO

index(3), memchr(3), rindex(3), strchr(3), strpbrk(3), strsep(3), strspn(3), strtok(3)