Setmonitor

["John R. Anderson", VLD/ASB]

	I am trying to use the "setmonitor" routine to switch our 4D to
30 Hz, sync on green mode while I grab the video with another device.
I wrote a very simple program to attempt this:

	#include <gl/gl.h>
	#include <gl/get.h>


	main()
	{
		short mtype;
		int ch;

		mtype = HZ30_SG;
		setmonitor( mtype );	/* switch to 30 Hz */

		while( (ch=getchar()) != '\n' ); /* wait for a CR */

		mtype = HZ60;
		setmonitor( mtype );	/* switch back to normal */
	}



It compiles nicely, but upon execution I get an "invalid argument" error
message from both "setmonitor" calls.  Anyone run into this before?? Any
ideas on why this desn't work??



				Thanks,
				-John