@node setmode, io
@subheading Syntax

@example
#include <io.h>

int setmode(int file, int mode);
@end example

@subheading Description


This function sets the mode of the given @var{file} to @var{mode}, which
is either @code{O_TEXT} or @code{O_BINARY}.  It will also set the file
into either cooked or raw mode accordingly, and set any @code{FILE*}
objects that use this file into text or binary mode. 

When called to put @var{file} that refers to the console into binary
mode, @code{setmode} will disable the generation of the signals
@code{SIGINT} and @code{SIGQUIT} when you press, respectively,
@kbd{Ctrl-@key{C}} and @kbd{Ctrl-@key{\}} (@kbd{Ctrl-@key{BREAK}} will
still cause @code{SIGINT}), because many programs that use binary reads
from the console will also want to get the @samp{^C} and @samp{^\} keys.
You can use the  @code{__djgpp_set_ctrl_c} library function
(@pxref{__djgpp_set_ctrl_c}) if you want @kbd{Ctrl-@key{C}} and
@kbd{Ctrl-@key{\}} to generate signals while console is read in
binary mode.

Note that, for buffered streams (@code{FILE*}), you must call
@code{fflush} (@pxref{fflush}) before @code{setmode}, or call
@code{setmode} before writing anything to the file, for proper
operation.

@subheading Return Value

When successful, the function will return the previous mode of the
given @var{file}.  In case of failure, -1 is returned and @var{errno}
is set.

@subheading Portability

@portability !ansi, !posix

@subheading Example

@example
setmode(0, O_BINARY);
@end example