Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help 
STRSTR(3)		    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 *big, const char *little);

       char *
       strcasestr(const	char *big, const char *little);

       char *
       strnstr(const char *big,	const char *little, size_t len);

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

       char *
       strcasestr_l(const char *big, const char	*little, locale_t loc);

DESCRIPTION
       The  strstr()  function locates the first occurrence of the null-termi-
       nated string little in the null-terminated string big.

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

       The  strcasestr_l() function does the same as strcasestr() but takes an
       explicit	locale rather than using the current locale.

       The strnstr() function locates the first	occurrence of the  null-termi-
       nated  string little in the string big, where not more than len charac-
       ters are	searched.  Characters that appear after	a `\0'	character  are
       not  searched.  Since the strnstr() function is a FreeBSD specific API,
       it should only be used when portability is not a	concern.

RETURN VALUES
       If little is an empty string, big is returned; if little	occurs nowhere
       in big, NULL is returned; otherwise a pointer to	the first character of
       the first occurrence of little 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)

STANDARDS
       The strstr() function conforms to ISO/IEC 9899:1990 ("ISO C90").

HISTORY
       The  strnstr()  function	was introduced by FreeBSD 4.5 and is non-stan-
       dard.

FreeBSD	14.3		       October 11, 2001			     STRSTR(3)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=strnstr&sektion=3&manpath=FreeBSD+14.3-RELEASE+and+Ports>

home | help