Defined in header <uchar.h> (since C11)
Defined in header <wchar.h>
struct mbstate_t;
(since C95)

The type mbstate_t is a trivial non-array type that can represent any of the conversion states that can occur in an implementation-defined set of supported multibyte character encoding rules. Zero-initialized value of mbstate_t represents the initial conversion state, although other values of mbstate_t may exist that also represent the initial conversion state.

Possible implementation of mbstate_t is a struct type holding an array representing the incomplete multibyte character, an integer counter indicating the number of bytes in the array that have been processed, and a representation of the current shift state.

The following functions should not be called from multiple threads without synchronization with the mbstate_t* argument of NULL due to possible data races: mbrlen, mbrtowc, mbsrtowcs, mbtowc, wcrtomb, wcsrtombs, wctomb.


  • C11 standard (ISO/IEC 9899:2011):
    • 7.29.1/2 Introduction (p: 402)
  • C99 standard (ISO/IEC 9899:1999):
    • 7.24.1/2 Introduction (p: 348)

See also

checks if the mbstate_t object represents initial shift state
C++ documentation for mbstate_t

© cppreference.com
Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.