strcasestr

SYNOPSIS
       #include <string.h>

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

       #define _GNU_SOURCE

       #include <string.h>

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

DESCRIPTION
       The  strstr() function finds the first occurrence of the substring nee-
       dle in the string haystack.  The terminating '\0'  characters  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 substring,  or
       NULL if the substring is not found.

CONFORMING TO
       The  strstr() function conforms to C89 and C99.  The strcasestr() func-
       tion is a non-standard extension.

BUGS
       Early versions of Linux libc (like 4.5.26) would  not  allow  an  empty
       needle  argument  for strstr().  Later versions (like 4.6.27) work cor-
       rectly, and return haystack when needle is empty.

SEE ALSO
       index(3), memchr(3), rindex(3), strcasecmp(3),  strchr(3),  strpbrk(3),
       strsep(3), strspn(3), strtok(3), wcsstr(3), feature_test_macros(7)

COLOPHON
       This  page  is  part of release 3.23 of the Linux man-pages project.  A
       description of the project, and information about reporting  bugs,  can
       be found at http://www.kernel.org/doc/man-pages/.



GNU                               2005-04-05                         STRSTR(3)