mbtowc()
Convert a multibyte character into a wide character
Synopsis:
#include <stdlib.h> int mbtowc( wchar_t * pwc, const char * s, size_t n );
Arguments:
- pwc
- A pointer to a wchar_t object where the function can store the wide character.
- s
- NULL (see below), or a pointer to the multibyte character that you want to convert.
- n
- The maximum number of bytes in the multibyte character to convert.
Library:
libc
Use the -l c option to qcc to link against this library. This library is usually included automatically.
Description:
The mbtowc() function converts a single multibyte character pointed to by s into a wide-character code pointed to by pwc, to a maximum of n bytes. The function stops early if it encounters the NULL character.
This function is affected by LC_TYPE.
The mbrtowc() function is a restartable version of mbtowc().
Returns:
- If s is NULL:
- 0
- The mbtowc() function uses UTF-8 multibyte character encoding that's not state-dependent.
- ≠ 0
- Everything else.
- If s isn't NULL:
- 0
- The s argument points to the NUL character.
- > 0
- The number of bytes that comprise the multibyte character, to a maximum of MB_CUR_MAX (if the next n or fewer bytes form a valid multibyte character).
- -1
- The next n bytes don't form a valid multibyte character; errno is set.
Errors:
- EILSEQ
- Invalid character sequence.
Examples:
#include <stdio.h> #include <stdlib.h> int main( void ) { char *wc = "string"; wchar_t wbuffer[10]; int i, len; printf( "State-dependent encoding? " ); if( mbtowc( wbuffer, NULL, 0 ) ) { printf( "Yes\n" ); } else { printf( "No\n" ); } len = mbtowc( wbuffer, wc, 2 ); wbuffer[len] = '\0'; printf( "%s(%d)\n", wc, len ); for( i = 0; i < len; i++ ) { printf( "/%4.4x", wbuffer[i] ); } printf( "\n" ); return EXIT_SUCCESS; }
This produces the output:
State-dependent encoding? No string(1) /0073
Classification:
Safety: | |
---|---|
Cancellation point | No |
Interrupt handler | No |
Signal handler | Yes |
Thread | Yes |