FWIDE(3) Library Functions Manual FWIDE(3)

fwideget/set orientation of a stream

Standard C Library (libc, -lc)

#include <stdio.h>
#include <wchar.h>

int
fwide(FILE *stream, int mode);

The () function determines the orientation of the stream pointed at by stream.

If the orientation of stream has already been determined, () leaves it unchanged. Otherwise, fwide() sets the orientation of stream according to mode.

If mode is less than zero, stream is set to be byte-oriented. If mode is greater than zero, stream is set to be wide-oriented. Otherwise, mode is zero, and stream is unchanged.

The fwide() function returns a value according to orientation after the call of fwide(); a value less than zero if byte-oriented, a value greater than zero if wide-oriented, and zero if the stream has no orientation.

ferror(3), fgetc(3), fgetwc(3), fopen(3), fputc(3), fputwc(3), freopen(3), stdio(3)

The fwide() function conforms to ISO/IEC 9899:1999 (“ISO C99”).

October 24, 2001 macOS 15.2