strstr, strcasestr, strnstr -- locate a substring in a string
Standard C Library (libc, -lc)
#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);
The strstr() function locates the first occurrence of the null-terminated
string little in the null-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 null-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 FreeBSD specific API, it
should only be used when portability is not a concern.
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.
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);
memchr(3), strchr(3), strcspn(3), strpbrk(3), strrchr(3), strsep(3),
strspn(3), strtok(3)
The strstr() function conforms to ISO/IEC 9899:1990 (``ISO C89'').
FreeBSD 5.2.1 October 11, 2001 FreeBSD 5.2.1 [ Back ] |