LinuxQuestions.org - saving output from FIFO?

Hello, i have a little problem, i have to filter the incoming text from a FIFO, and save it to a file, so i do:

Code:

root@linux-it:/path/to/fifos# cat debug.fifo | grep -v traffic > file

and /path/to/fifos/file is created, but with no contents :S if i do:

Code:

root@linux-it:/path/to/fifos# cat debug.fifo | grep -v traffic

the output from the fifo is filtered and displayed correctly, but i cant save it :S
and if i execute:

Code:

root@linux-it:/path/to/fifos# cat debug.fifo > file

the output gets correctly saved to the file...

(im sure this is a pretty stupid problem, but i dont know how to solve it...)

thanks!

EDIT: It's an issue with the '-v' option, if i exec

Code:

cat debug.fifo | grep Permit > file

it saves the file correctly, any walkarounds?