[net.micro.att] Obscure feature in PC7300 windows

root@bu-cs.UUCP (Barry Shein) (07/15/85)

Please tell me if I am wrong but if I create a new window and
immediately try to query it's size, it will be zero X zero as
in: (my actual code has more err checks, that's not the problem!)

#include <sys/window.h>

	struct uwdata uw ;

	close(0) ;
	open("/dev/window",2) ;
	close(1) ;
	close(2) ;
	dup(0) ;
	dup(0) ;	/* stdin, stdout and stderr are all in the window */

	ioctl(0,WIOCGETD,&uw) ;
	printf("%d X %d\n",uw_width,uw_height) ;

will print 0 X 0

If I add any output such as:

	write(1,"Hello World\n",12) ;
before the ioctl, then all is well, so, question:

does anyone know exactly what is going on here, like is there another
way to wake things up besides scribbling i/o? Is this a bug or a feature?

Thanks in advance.

	-Barry Shein, Boston University

P.S. Not serious, but confusing till ya figure out how to work-around.