NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | CONFORMING TO | BUGS | SEE ALSO | COLOPHON

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

NAME         top

       strstr, strcasestr - locate a substring

SYNOPSIS         top

       #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         top

       The strstr() function finds the first occurrence of the substring needle 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         top

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

CONFORMING TO         top

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

BUGS         top

       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 correctly, and
       return haystack when needle is empty.

SEE ALSO         top

       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         top

       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)