Power off QNX4 from shell?

Hi, could somebody explain how, in QNX4, I initiate a complete hardware poweroff, using a shell command? I see the “shutdown” command, but according to the included documentation, it just reboots the system. Looking through the archives here, I found “shutdown -fb” which makes the desktop disappear, but does not poweroff the computer.

It’s been a LONG time since I used QNX 4, but if I remember correctly its not done via the shutdown command but through options to Proc32.


The default is to reboot which you don’t want. So this would mean you’d need to be able to build new boot images for your systems which I suspect you probably can’t.

Maybe there is an option in the BIOS you might be able to set to do what you want.


Does building new boot images require the original installation media? Or something available on any live system?

I looked through the BIOS and there are APM and ACPI pages but I couldn’t find anything that seemed useful in regards to this problem.

Well, at least I can do “shutdown -b” which brings the system down to some kind of halted state, and then I can hit the power switch. But it would be more ideal if shutdown would power off as well. I tried “-a, -c, -d, etc.” but didn’t find any other undocumented flags.

Yes, new boot images would require the original installation media.

The full power down that you want is going to involve the O/S interacting with the BIOS. That’s why you’d need a new boot image with Proc32.

Usually somewhere in the BIOS menu there is an option for what happens when you press the power button. Whether it powers off, reboots, needs a long press etc. Hopefully that’s exposed to the user and not just hidden commands only available to the O/S.