strstr(3) — Linux manual page


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         /* See feature_test_macros(7) */

       #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 null bytes ('\0') 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 located
       substring, or NULL if the substring is not found.

ATTRIBUTES         top

       For an explanation of the terms used in this section, see

       │Interface    Attribute     Value          │
       │strstr()     │ Thread safety │ MT-Safe        │
       │strcasestr() │ Thread safety │ MT-Safe locale │

CONFORMING TO         top

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

       The strcasestr() function is a nonstandard extension.

SEE ALSO         top

       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         top

       This page is part of release 5.08 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

GNU                              2019-03-06                        STRSTR(3)

Pages that refer to this page: index(3)memchr(3)memmem(3)memrchr(3)rawmemchr(3)rindex(3)strchr(3)strchrnul(3)strcspn(3)string(3)strpbrk(3)strrchr(3)strsep(3)strspn(3)strtok(3)strtok_r(3)wcsstr(3)signal-safety(7)