#include <wchar.h>
   wint_t btowc(int);

convert a byte to wide character btowc returns the wide two byte character “wchar_t” converted from the single byte “string” character (char).

If the argument is not a valid multibyte sequence of length 1 btowc returns WEOF.
output is affected by the current LC_TYPE locale.

/* 
 * btowc example code
 * http://code-reference.com/c/wchar.h/btowc
 */
 
#include <stdio.h>
#include <wchar.h>
 
int main( void ) {
 
    char string[] = "btowc \x65xampl\x65";
    int i;
 
    for ( i = 0; i < 13; ++i) {
        printf("%c %c\n", string[i], (wchar_t)btowc(string[i]) );
    }
    return 0;
}

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