STRSTR(3) | FreeBSD Library Functions Manual | STRSTR(3) |
NAME
strstr, strcasestr, strnstr — locate a substring in a stringLIBRARY
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-terminated 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-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.
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”).October 11, 2001 | FreeBSD |