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When I type xlock and press return key, I am getting the following error:

Unknown mode: xlock:  bad command line option "swarm"

What should I do? I just need the basic xlock screen locking functionality.

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up vote 1 down vote accepted

'xlock' is trying to run the 'swarm' display mode (rather than simply blanking the screen) and is doing it wrong.

Maybe you are running

xlock -swarm

instead of

xlock -mode swarm

Or is it that your xlock hasn't been compiled/configured with the swarm screensaver on your system?

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I am just typing xlock. I have no idea whether it is configured or not. I just want the basic xlock locking functionality. What should I do? – Lazer Jan 23 '10 at 20:11
try xlock -mode dclock or (i think) xlock -mode blank – user23307 Jan 23 '10 at 21:34
thanks! xlock -mode blank works! – Lazer Jan 25 '10 at 3:42

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