Setsid execute on another tty and log the output

pedropt · 11-23-2019, 01:15 PM

i have been trying to figure why i can not get an output log from another terminal when i launch some script with its output to a file .

when i :

Quote:

setsid sh -c "exec somecommand > log <> /dev/tty9 >&0 2>&1" &

i get the tty opened with the command , but i am unable to get anything on the log file .

even if i :

Quote:

setsid sh -c "exec somecommand | tee log <> /dev/tty9 >&0 2>&1" &

i still can not get the log file from that command .

What happens is that log file is created but it is empty

I am launching setsid from another script , so that is why i have the switch "-c" .

NevemTeve · 11-23-2019, 01:32 PM

Perhaps you want sg like this:

Code:

trap '' HUP
command 2>&1 | tee logfile >/dev/tty9

pedropt · 11-23-2019, 02:05 PM

nop , i still need the current master script running while tty9 is opened .
that command you wrote is good for this example :

Quote:

trap '' HUP
ls / 2>&1 | tee logfile >/dev/tty9

but if i need to run netcat on tty9 that will need additional commands then i am stuck .

NevemTeve · 11-23-2019, 02:41 PM

That's what an &ampersand is good for.
Also there is command openvt:

Code:

openvt -- sh -c 'command | tee logfile’

https://linux.die.net/man/1/openvt