strspn, wcsspn, _mbsspn
Returns the index of the first character in a string that does not belong to a set of characters.
size_t strspn( const char *string, const char *strCharSet ); size_t wcsspn( const wchar_t *string, const wchar_t *strCharSet ); size_t _mbsspn( const unsigned char *string, const unsigned char *strCharSet );
Parameters
- string
- Null-terminated string to search.
- strCharSet
- Null-terminated character set.
Return Value
Returns an integer value specifying the length of the substring in string that consists entirely of characters in strCharSet. If string begins with a character not in strCharSet, the function returns 0. No return value is reserved to indicate an error.
Remarks
The strspn function returns the index of the first character in string that does not belong to the set of characters in strCharSet. The search does not include terminating null characters.
wcsspn and _mbsspn are wide-character and multibyte-character versions of strspn. The arguments of wcsspn are wide-character strings; those of _mbsspn are multibyte-character strings. These three functions behave identically otherwise.
Generic-Text Routine Mappings
| TCHAR.H routine | _UNICODE & _MBCS not defined | _MBCS defined | _UNICODE defined |
|---|---|---|---|
| _tcsspn | strspn | _mbsspn | wcsspn |
Requirements
| Routine | Required header | Compatibility |
|---|---|---|
| strspn | <string.h> | ANSI, Win 98, Win Me, Win NT, Win 2000, Win XP |
| wcsspn | <string.h> or <wchar.h> | ANSI, Win 98, Win Me, Win NT, Win 2000, Win XP |
| _mbsspn | <mbstring.h> | Win 98, Win Me, Win NT, Win 2000, Win XP |
For additional compatibility information, see Compatibility in the Introduction.
Libraries
All versions of the C run-time libraries.
Example
// crt_strspn.c
/* This program uses strspn to determine
* the length of the segment in the string "cabbage"
* consisting of a's, b's, and c's. In other words,
* it finds the first non-abc letter.
*/
#include <string.h>
#include <stdio.h>
int main( void )
{
char string[] = "cabbage";
int result;
result = strspn( string, "abc" );
printf( "The portion of '%s' containing only a, b, or c "
"is %d bytes long\n", string, result );
}
Output
The portion of 'cabbage' containing only a, b, or c is 5 bytes long
See Also
String Manipulation Routines | _mbsspnp | strcspn | strncat | strncmp | strncpy | _strnicmp | strrchr | Run-Time Routines and .NET Framework Equivalents
