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MBSINIT(3) Linux Programmer's Manual MBSINIT(3)
mbsinit - test for initial shift state
#include <wchar.h>
int mbsinit(const mbstate_t *ps);
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(mbstate_t));
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.
mbsinit() returns nonzero if *ps is an initial state, or if ps is a null
pointer. Otherwise it returns 0.
C99.
The behavior of mbsinit() depends on the LC_CTYPE category of the current
locale.
mbsrtowcs(3), wcsrtombs(3)
This page is part of release 3.32 of the Linux man-pages project. A
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at http://www.kernel.org/doc/man-pages/.
GNU 2000-11-20 MBSINIT(3)
HTML rendering created 2010-12-03 by Michael Kerrisk, author of The Linux Programming Interface