strstr

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



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
       For an explanation of the terms used in this section, see
       attributes(7).

       ┌─────────────┬───────────────┬────────────────┐
       │Interface    Attribute     Value          │
       ├─────────────┼───────────────┼────────────────┤
       │strstr()     │ Thread safety │ MT-Safe        │
       ├─────────────┼───────────────┼────────────────┤
       │strcasestr() │ Thread safety │ MT-Safe locale │
       └─────────────┴───────────────┴────────────────┘
CONFORMING TO
       strstr(): POSIX.1-2001, POSIX.1-2008, C89, C99.

       The strcasestr() function is a nonstandard extension.

SEE ALSO
       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
       This page is part of release 5.06 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
       https://www.kernel.org/doc/man-pages/.



GNU                               2019-03-06                         STRSTR(3)