console_ctrl()

set bits in the control word for a console

Synopsis:

#include <sys/console.h>
unsigned console_ctrl( struct _console_ctrl *cc,
                       int console,
                       unsigned bits,
                       unsigned mask );

Description:

The console_ctrl() function sets any bits in the console control word for this console that are indicated in mask to be the corresponding value given in bits.

The previous, unmodified control word is returned.

Console control bits are defined in <sys/console.h>, and include at least the following:

CONSOLE_NOBOOT: Disable reboot from keyboard.
CONSOLE_NOSWITCH: Disable console switching from keyboard.
CONSOLE_NODEBUG: Disable debug entry from keyboard.
CONSOLE_NORESIZE: Disable display re-sizing from keyboard.
CONSOLE_NOCOLOR: Disable colors on the display.
CONSOLE_MONOCURS: Force the display cursor to be the size of a cursor on a monochrome display.
CONSOLE_SCANMODE: Enable scanmode key codes (see the QNX User's Guide).
CONSOLE_EXTMODE: Enable extended key codes (see the QNX User's Guide).

Returns:

The previous, unmodified control word. If an error is encountered, -1 is returned and errno is set.

Errors:

EACCES: You don't have permission to affect the specified console.
EINVAL: The control structure is in the wrong format.
ENXIO: The console value is invalid.

Examples:

#include <sys/console.h>
#include <fcntl.h>
#include <unistd.h>

int main( void )
  {
    struct _console_ctrl *cc;
    int fd, old;

    /*
     * Open up a channel to the console driver
     */
    fd = open( "/dev/con1", O_RDWR );
    cc = console_open( fd, O_RDWR );
    close( fd );

    /*
     * Suppress console switching
     */
    old = console_ctrl( cc, 0,
        CONSOLE_NOSWITCH, CONSOLE_NOSWITCH );

    /*
     * Restore console switching to previous state
     */
    console_ctrl( cc, 0, old, CONSOLE_NOSWITCH );
    /*
     * Close the channel
     */
    console_close( cc );
    return (EXIT_SUCCESS);
  }

Classification:

QNX

Safety:
Interrupt handler	No
Signal handler	Yes, but modifies errno
Thread	Yes