strstr(3) [debian man page]

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 ('') 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() function is a nonstandard 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), string(3), strpbrk(3), strsep(3), strspn(3), strtok(3), wcsstr(3)

COLOPHON

       This  page is part of release 3.44 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
								    2011-09-28								 STRSTR(3)

STRSTR(3)						   BSD Library Functions Manual 						 STRSTR(3)

NAME

     strstr, strcasestr, strnstr -- locate a substring in a string

LIBRARY

     Standard C Library (libc, -lc)

SYNOPSIS

     #include <string.h>

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

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

     char *
     strnstr(const char *haystack, const char *needle, size_t len);

     #include <string.h>
     #include <xlocale.h>

     char *
     strcasestr_l(const char *haystack, const char *needle, locale_t loc);

DESCRIPTION

     The strstr() function locates the first occurrence of the null-terminated string needle in the null-terminated string haystack.

     The strcasestr() function is similar to strstr(), but ignores the case of both strings.

     The strnstr() function locates the first occurrence of the null-terminated string needle in the string haystack, where not more than len
     characters are searched.  Characters that appear after a '' character are not searched.	Since the strnstr() function is a FreeBSD specific
     API, it should only be used when portability is not a concern.

     While the strcasestr() function uses the current locale, the strcasestr_l() function may be passed a locale directly. See xlocale(3) for more
     information.

RETURN VALUES

     If needle is an empty string, haystack is returned; if needle occurs nowhere in haystack, NULL is returned; otherwise a pointer to the first
     character of the first occurrence of needle is returned.

EXAMPLES

     The following sets the pointer ptr to the "Bar Baz" portion of largestring:

	   const char *largestring = "Foo Bar Baz";
	   const char *smallstring = "Bar";
	   char *ptr;

	   ptr = strstr(largestring, smallstring);

     The following sets the pointer ptr to NULL, because only the first 4 characters of largestring are searched:

	   const char *largestring = "Foo Bar Baz";
	   const char *smallstring = "Bar";
	   char *ptr;

	   ptr = strnstr(largestring, smallstring, 4);

SEE ALSO

     memchr(3), memmem(3), strchr(3), strcspn(3), strpbrk(3), strrchr(3), strsep(3), strspn(3), strtok(3), wcsstr(3), xlocale(3)

STANDARDS

     The strstr() function conforms to ISO/IEC 9899:1990 (``ISO C90'').

BSD
								 October 11, 2001							       BSD