_ismbslead, _ismbstrail, _ismbslead_l, _ismbstrail_l

Perform context-sensitive tests for multibyte-character string lead and trail bytes and determine whether a given substring pointer points to a lead byte or a trail byte.

int _ismbslead(
   const unsigned char *str,
   const unsigned char *current 
);
int _ismbstrail(
   const unsigned char *str,
   const unsigned char *current 
);
int _ismbslead_l(
   const unsigned char *str,
   const unsigned char *current,
   _locale_t locale
);
int _ismbstrail_l(
   const unsigned char *str,
   const unsigned char *current,
   _locale_t locale
);

Parameters

• str
  Pointer to the start of the string or previous known lead byte.

• current
  Pointer to the position in the string to be tested.

• locale
  Locale to use.

Return Value

_ismbsleadand _ismbstrailreturn –1 if the character is a lead or trail byte, respectively. If the input strings are valid strings but not a lead or trail byte, these functions return zero. If either argument is NULL, the invalid parameter handler is invoked, as described in Parameter Validation. If execution is allowed to continue, these functions return NULL and set errno to EINVAL.

Remarks

_ismbslead and _ismbstrail are slower than the _ismbblead and _ismbbtrail versions because they take the string context into account.

The versions of these functions with the _l suffix are identical except that they use the locale passed in instead of the current locale for their locale-dependent behavior. For more information, see Locale.

Requirements

* For manifest constants for the test conditions.

For more compatibility information, see Compatibility in the Introduction.

.NET Framework Equivalent

Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.

See Also

Reference

Character Classification

_ismbc Routines

is, isw Routines

_ismbb Routines