Hello, I run MCNlive from USB drive and I want to create a swap file on the same USB drive. Is it possible?

it IS possible, ive just never found it needed.

boot from your stick, go to mcc and partition is as you would any other disk, you may lose everything on your LAST partiton, i did this once and my setup was this:

MCNL - DATA
700MB 1300MB

I then added a 200MB swap and it looked like this:

MCNL - SWAP - DATA
700MB 200MB 1100MB

but when i did that I was able to keep my MCNL, but I lost my DATA

Normally, any decent liveCD is automounting the local swap partition for its needs at bootup.
Even if it doesn't, you will rarely need it- unless the host machine is very anhaemic.

and as far as i can remember, using a flash-based space for swap is not recommended since that will expedite the "wear" on the storage system. some flash device manufacturers are working around this by incorporating some leveling algorithm that will spread the writes around the device.

like what scarecrow said, use a flash-based swap if the machine has very limited RAM, or use less memory intensive applications if you can.

to answer your original question, look at the manpage of the mkswap/swapon/swapoff commands.

ciao!

bad idea ... usb stick will die with in days I reckon

Thanks for all.