Detecting the current terminal

iphony has asked for the wisdom of the Perl Monks concerning the following question:

Hi Monks, I have a script which runs automatically when the user logs on. Sometimes the user may logon via the console (tty) sometimes via remotely via network (pts). E.g.

[root@localhost ~]# who
root     tty1         Nov 12 15:48
root     pts/0        Nov 12 15:51 (10.10.20.13)
[download]

How can the perl script detects which terminal it's currently running on? Thanks.

Comment on Detecting the current terminal Download Code

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Re: Detecting the current terminal by Fletch (Bishop) on Nov 12, 2008 at 14:34 UTC
If you're looking for OS interaction POSIX is (usually, most of the time :) your friend . . . `$ perl -MPOSIX=ttyname -le 'print "I am on tty ", ttyname(STDIN);' I am on tty /dev/pts/34 $ tty /dev/pts/34` [download] The cake is a lie. The cake is a lie. The cake is a lie.	[reply] [d/l]
Re: Detecting the current terminal by pjotrik (Friar) on Nov 12, 2008 at 09:08 UTC
Just an idea: `who -a` gives PID of the login process in addition. From the PID of your script, you could traverse the parent-pid hierarchy (through `ps -f --pid xxx` or some handy module), until you find one listed in the `who -a`.	[reply] [d/l] [select]
Re: Detecting the current terminal by shmem (Chancellor) on Nov 12, 2008 at 14:42 UTC
chop (my $tty = `tty`); if ($tty =~ /tty\d/) { # console ... } else { # network ... } [download]	[reply] [d/l]
Re: Detecting the current terminal by Anonymous Monk on Nov 12, 2008 at 09:38 UTC
Why would the script care?	[reply]
Re^2: Detecting the current terminal by iphony (Acolyte) on Nov 12, 2008 at 09:42 UTC
It's because some functions would be disabled if the user is running the script remotely.	[reply]
Re^3: Detecting the current terminal by Anonymous Monk on Nov 13, 2008 at 07:50 UTC
web servers set some special %ENV values, don't remote terminal servers do the same?	[reply]