NAME
strstr,
strcasestr, strnstr —
locate a substring in a
string
LIBRARY
library “libc”
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);
DESCRIPTION
Thestrstr()
function locates the first occurrence of the nul-terminated string
little in the nul-terminated string
big.
The
strcasestr()
function is similar to strstr(), but ignores the
case of both strings. The
strnstr()
function locates the first occurrence of the NUL-terminated string
little in the string big, where
not more than len characters are searched. Characters
that appear after a ‘\0’ character are
not searched. Since the strnstr() function is a
NetBSD 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);
SEE ALSO
index(3), memchr(3), rindex(3), strchr(3), strcspn(3), strpbrk(3), strrchr(3), strsep(3), strspn(3), strtok(3)
STANDARDS
The strstr() function conforms to
ISO/IEC 9899:1990
(“ISO C90”).
HISTORY
The strnstr() function originated in
FreeBSD.