fwide():
_XOPEN_SOURCE >= 500 || _ISOC99_SOURCE; or
cc -std=c99
DESCRIPTION
When mode is zero, the
fwide()
function determines the current
orientation of stream.
It returns a positive value if stream is
wide-character oriented, that is, if wide-character I/O is permitted but char
I/O is disallowed.
It returns a negative value 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 is greater than 0, or
to byte oriented if mode is less than 0).
It then returns a value denoting the
current orientation, as above.
RETURN VALUE
The
fwide()
function returns the stream's orientation, after possibly
changing it.
A positive return value means wide-character oriented.
A negative return value means byte oriented.
A return value of zero means undecided.
CONFORMING TO
C99, POSIX.1-2001.
NOTES
Wide-character output to a byte oriented stream can be performed through the
fprintf(3)
function with the
%lc
and
%ls
directives.
Char oriented output to a wide-character oriented stream can be performed
through the
fwprintf(3)
function with the
%c
and
%s
directives.
This page is part of release 3.14 of the Linux
man-pages
project.
A description of the project,
and information about reporting bugs,
can be found at
http://www.kernel.org/doc/man-pages/.
