On Jul 9, 2005, at 8:38 PM, Karsten Kruse wrote:

> Dan LaBell wrote:
>
>> Is there a chvt or equivalent way to change from one virtual screen to
>> another another , programmatically ? Any ioctl or other os interface?
>> I'm guessing stuffing the terminal input buffer via TIOCSTI will not
>> work ( wrong layer, not low enough ).
>
> http://mail-index.netbsd.org/netbsd-users/2002/11/13/0007.html
>
> Works for me.
>

Thanks,  I needed: options         WSDISPLAY_COMPAT_USL
for the ioctl, I had trimmed it, thinking it was just another 
compatibility feature.
After adding it, it worked fine, and I don't think I could have 
understand it w/o sample code.

I was kinda of hoping there would be something in the form of taking a 
file descriptor
to the vt, rather than passing the screen number.  So instead of:
   fd=open("/dev/ttyECfg", O_RDWR, 0 );
   ioctl(fd,VT_ACTIVATE,screen);
something like:
   fd=open("/dev/ttyE1", O_RDRW, 0);
   ioctl(fd, VT_ACTIVATE);   /* *** */
leading to a shell-util where one could just do vtactivate $( tty ),
or possibly, it could just take /dev/tty, or straight STDIN_FILENO.

Of course, I could wrap it, to get that idiom, which I guess I'll leave 
as an exercise to myself.