isleadbyte, _isleadbyte_l

Determine if a character is the lead byte of a multibyte character.

Important

This API cannot be used in applications that execute in the Windows Runtime. For more information, see CRT functions not supported with /ZW.

int isleadbyte(
   int c 
);
int _isleadbyte_l(
   int c 
);

Parameters

  • c
    Integer to test.

Return Value

isleadbyte returns a nonzero value if the argument satisfies the test condition or 0 if it does not. In the "C" locale and in single-byte character set (SBCS) locales, isleadbyte always returns 0.

Remarks

The isleadbyte macro returns a nonzero value if its argument is the first byte of a multibyte character. isleadbyte produces a meaningful result for any integer argument from –1 (EOF) to UCHAR_MAX (0xFF), inclusive.

The expected argument type of isleadbyte is int; if a signed character is passed, the compiler may convert it to an integer by sign extension, yielding unpredictable results.

The version of this function with the _l suffix is identical except that it uses the locale passed in instead of the current locale for its locale-dependent behavior.

Generic-Text Routine Mappings

TCHAR.H routine

_UNICODE & _MBCS not defined

_MBCS defined

_UNICODE defined

_istleadbyte

Always returns false

_isleadbyte

Always returns false

Requirements

Routine

Required header

isleadbyte

<ctype.h>

_isleadbyte_l

<ctype.h>

For additional compatibility information, see Compatibility in the Introduction.

.NET Framework Equivalent

Not applicable, but see System::Globalization::CultureInfo.

See Also

Reference

Byte Classification

Locale

_ismbb Routines