GENWiki

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 nee-
     dle 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  sub-
     string, or NULL if the substring is not found.

ATTRIBUTES

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

     allbox;  lb  lb  lb  l  l  l.   Interface Attribute Value  T{  strstr()
     T}   Thread  safety    MT-Safe  T{ strcasestr() T}   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 4.16 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 2017-09-15 STRSTR(3)