george@wciu.wciu.edu (George Peavy) (03/20/91)
I'm still learning shell programming, and have hit a snag that, so far, I
haven't been able to figure out.
Here's what's happening: I'm writing a menu program that, among other things,
allows a user to select the option of up/downloading files to/from a PC.
Since I also have terminals attached, I want to disallow this option unless
the user is working from a port known to have a pc attached to it.
What I have so far: I'm using Bourne shell on AT&T Sys V 3.0 running on a
Unisys 6000/51 platform. I can get the port id with,
who am i | awk '{ print $2 }'
The question is, how do I get this information into a place where I can
test the value? Is there a simpler way than my use of awk?
posted(and I hope I've gotten the right group for followup) and email
replies both welcomed.
Thanks in advance.
--
George Peavy
(george@wciu.edu)jik@athena.mit.edu (Jonathan I. Kamens) (03/20/91)
(Note: "Followup-To: comp.unix.questions, george@wciu.edu" is not valid for two reasons. The first is that there shouldn't be any spaces in it. And the second is that you can't put E-mail addresses in the Followup-To line. You must put either a list of newsgroups or the word "poster" to ask for E-mail replies only.) In article <1991Mar19.171708.18628@wciu.EDU>, george@wciu.wciu.edu (George Peavy) writes: |> What I have so far: I'm using Bourne shell on AT&T Sys V 3.0 running on a |> Unisys 6000/51 platform. I can get the port id with, |> |> who am i | awk '{ print $2 }' |> |> The question is, how do I get this information into a place where I can |> test the value? Is there a simpler way than my use of awk? If you really want to use awk, then you can use backquotes to evaluate the command above and assign its output to a variable, e.g. tty=`who am i | awk '{ print $2 }'` However, it seems to me that the "tty" command will give you the same information, and only requires one process: tty=`tty` The output of tty will have "/dev/" at the front of it (assuming that your devices are in /dev :-), but you can cope with that rather trivially. -- Jonathan Kamens USnail: MIT Project Athena 11 Ashford Terrace jik@Athena.MIT.EDU Allston, MA 02134 Office: 617-253-8085 Home: 617-782-0710
rad@genco.bungi.com (Bob Daniel) (03/22/91)
In article <1991Mar19.171708.18628@wciu.EDU> george@wciu.wciu.edu (George Peavy) writes: > >What I have so far: I'm using Bourne shell on AT&T Sys V 3.0 running on a >Unisys 6000/51 platform. I can get the port id with, > > who am i | awk '{ print $2 }' > This is how I do it... device=`tty` port=`basename $device` echo $port The "`" are accent marks, not single quotes. I'm on AT&T SysV 3.2.3. This is also more accurate than using 'who am i' when using 'layers'.
rad@genco.bungi.com (Bob Daniel) (03/22/91)
In article <1991Mar19.171708.18628@wciu.EDU> george@wciu.wciu.edu (George Peavy) writes: >I'm still learning shell programming, and have hit a snag that, so far, I >haven't been able to figure out. > >Here's what's happening: I'm writing a menu program that, among other things, >allows a user to select the option of up/downloading files to/from a PC. >Since I also have terminals attached, I want to disallow this option unless >the user is working from a port known to have a pc attached to it. > > > who am i | awk '{ print $2 }' > >The question is, how do I get this information into a place where I can >test the value? Is there a simpler way than my use of awk? This is how I do it... device=`tty` port=`basename $device` if [ "$port" = "ttyXX" ] then ... fi or instead of 'if'.... case $port in ttyX1) foo1;; ttyX2) foo2;; etc) fooX;; esac ______ The ` is accent marks, not single quotations. I'm using AT&T SysV 3.2.3 so this should work for you.