Originální popis anglicky:
fwide - set and determine the orientation of a FILE stream
Návod, kniha: Linux Programmer's Manual
#include <wchar.h>
int fwide(FILE *stream, int mode);
When
mode is zero, the
fwide function determines the current
orientation of
stream. It returns a value > 0 if
stream is
wide-character oriented, i.e. if wide character I/O is permitted but char I/O
is disallowed. It returns a value < 0 if
stream is byte oriented,
i.e. if char I/O is permitted but wide character I/O is disallowed. It returns
zero if
stream has no orientation yet; in this case the next I/O
operation might change the orientation (to byte oriented if it is a char I/O
operation, or to wide-character oriented if it is a wide character I/O
operation).
Once a stream has an orientation, it cannot be changed and persists until the
stream is closed.
When
mode is non-zero, the
fwide function first attempts to set
stream's orientation (to wide-character oriented if
mode > 0,
or to byte oriented if
mode < 0). It then returns a value denoting
the current orientation, as above.
The
fwide function returns the stream's orientation, after possibly
changing it. A return value > 0 means wide-character oriented. A return
value < 0 means byte oriented. A return value zero means undecided.
ISO/ANSI C, UNIX98
fprintf(3),
fwprintf(3)
Wide-character output to a byte oriented stream can be performed through the
fprintf function with the %lc and %ls directives.
Char oriented output to a wide-character oriented stream can be performed
through the
fwprintf function with the %c and %s directives.
