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Changing tty's in perl

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Contributed by Zombie falken on Aug 11, 2001 at 02:50 UTC
Q&A  > input and output


Description:

I have an application that i'm executing with in perl with the system("cmd &") call. For some reason it is requiring it have STDIN. I have closed all STDIN, STDOUT STDERR fd's and tried the POSIX setsid(). All with no luck. Is there anyway in perl I can switch the tty with posix functions and (or) fool the application into a another non-used tty?

Answer: Changing tty's in perl
contributed by kjherron

The posix way to obtain a new controlling tty is to first get rid of the old one, as you've outlined, and then open a new one; the first one opened becomes the new controlling tty. You can't use "/dev/tty" for this purpose of course, you'd have to open a real tty device. These are /dev/pty*, /dev/console, and devices corresponding to actual serial ports.

Is the program insisting on a tty, or just a valid stdin? Instead of just closing stdin/stdout/stderr you can try opening them to /dev/null, and see if that is sufficient. If it needs a tty, one can often use /dev/console.

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