проверка начального состояния смены (test for initial shift state)
Имя (Name)
mbsinit - test for initial shift state
Синопсис (Synopsis)
#include <wchar.h>
int mbsinit(const mbstate_t *
ps);
Описание (Description)
Character conversion between the multibyte representation and the
wide character representation uses conversion state, of type
mbstate_t. Conversion of a string uses a finite-state machine;
when it is interrupted after the complete conversion of a number
of characters, it may need to save a state for processing the
remaining characters. Such a conversion state is needed for the
sake of encodings such as ISO-2022 and UTF-7.
The initial state is the state at the beginning of conversion of
a string. There are two kinds of state: the one used by
multibyte to wide character conversion functions, such as
mbsrtowcs(3), and the one used by wide character to multibyte
conversion functions, such as wcsrtombs(3), but they both fit in
a mbstate_t, and they both have the same representation for an
initial state.
For 8-bit encodings, all states are equivalent to the initial
state. For multibyte encodings like UTF-8, EUC-*, BIG5, or SJIS,
the wide character to multibyte conversion functions never
produce non-initial states, but the multibyte to wide-character
conversion functions like mbrtowc(3) do produce non-initial
states when interrupted in the middle of a character.
One possible way to create an mbstate_t in initial state is to
set it to zero:
mbstate_t state;
memset(&state, 0, sizeof(state));
On Linux, the following works as well, but might generate
compiler warnings:
mbstate_t state = { 0 };
The function mbsinit
() tests whether *ps corresponds to an
initial state.
Возвращаемое значение (Return value)
mbsinit
() returns nonzero if *ps is an initial state, or if ps is
NULL. Otherwise, it returns 0.
Атрибуты (Attributes)
For an explanation of the terms used in this section, see
attributes(7).
┌──────────────────────────────────────┬───────────────┬─────────┐
│Interface
│ Attribute
│ Value
│
├──────────────────────────────────────┼───────────────┼─────────┤
│mbsinit
() │ Thread safety │ MT-Safe │
└──────────────────────────────────────┴───────────────┴─────────┘
Стандарты (Conforming to)
POSIX.1-2001, POSIX.1-2008, C99.
Примечание (Note)
The behavior of mbsinit
() depends on the LC_CTYPE
category of the
current locale.
Смотри также (See also)
mbrlen(3), mbrtowc(3), mbsrtowcs(3), wcrtomb(3), wcsrtombs(3)