strcspn, wcscspn, _mbscspn, _mbscspn_l
Returns the index of the first occurrence of a character in a string that belongs to a set of characters.
size_t strcspn( const char *str, const char *strCharSet ); size_t wcscspn( const wchar_t *str, const wchar_t *strCharSet ); size_t _mbscspn( const unsigned char *str, const unsigned char *strCharSet ); size_t _mbscspn( const unsigned char *str, const unsigned char *strCharSet, _locale_t locale );
wcscspn and _mbscspn are wide-character and multibyte-character versions of strcspn. The arguments of wcscspn are wide-character strings; those of _mbscspn are multibyte-character strings.
_mbscspn validates its parameters. If either str or strCharSet is a null pointer, the invalid parameter handler is invoked, as described in Parameter Validation. If execution is allowed to continue, the function returns 0 and sets errno to EINVAL. strcspn and wcscspn do not validate their parameters. These three functions behave identically otherwise.
The output value is affected by the setting of the LC_CTYPE category setting of the locale; see setlocale for more information. The versions of these functions without the _l suffix use the current locale for this locale-dependent behavior; the versions with the _l suffix are identical except that they use the locale parameter passed in instead. For more information, see Locale.
TCHAR.H routine | _UNICODE & _MBCS not defined | _MBCS defined | _UNICODE defined |
|---|---|---|---|
_tcscspn | strcspn | _mbscspn | wcscspn |
n/a | n/a | _mbscspn_l | n/a |
Routine | Required header |
|---|---|
strcspn | <string.h> |
wcscspn | <string.h> or <wchar.h> |
_mbscspn, _mbscspn_l | <mbstring.h> |
For additional compatibility information, see Compatibility in the Introduction.
// crt_strcspn.c
#include <string.h>
#include <stdio.h>
void test( const char * str, const char * strCharSet )
{
int pos = strcspn( str, strCharSet );
printf( "strcspn( \"%s\", \"%s\" ) = %d\n", str, strCharSet, pos );
}
int main( void )
{
test( "xyzbxz", "abc" );
test( "xyzbxz", "xyz" );
test( "xyzbxz", "no match" );
test( "xyzbxz", "" );
test( "", "abc" );
test( "", "" );
}
strcspn( "xyzbxz", "abc" ) = 3 strcspn( "xyzbxz", "xyz" ) = 0 strcspn( "xyzbxz", "no match" ) = 6 strcspn( "xyzbxz", "" ) = 6 strcspn( "", "abc" ) = 0 strcspn( "", "" ) = 0
