wcsspn

size_t wcsspn( const wchar_t* dest, const wchar_t* src );

Returns the length of the maximum initial segment of the wide string pointed to by dest, that consists of only the characters found in wide string pointed to by src.

Parameters

Return value

The length of the maximum initial segment that contains only characters from wide string pointed to by src.

Example

#include <locale.h>
#include <wchar.h>
 
int main(void)
{
    wchar_t dest[] = L"白猫 黑狗 甲虫";
    const wchar_t src[] = L" 狗猫 白黑 ";
    const size_t len = wcsspn(dest, src);
    dest[len] = L'\0'; /* terminates the segment to print it out */
 
    setlocale(LC_ALL, "en_US.utf8");
    wprintf(L"The length of maximum initial segment is %td.\n"
            L"The segment is \"%ls\".\n", len, dest);
}

The length of maximum initial segment is 6.
The segment is "白猫 黑狗 ".

References

• C11 standard (ISO/IEC 9899:2011):
• 7.29.4.5.5 The wcsspn function (p: 436)
• C99 standard (ISO/IEC 9899:1999):
• 7.24.4.5.5 The wcsspn function (p: 382)

See also