Login or Register to Ask a Question and Join Our Community

Sponsored Content
Full Discussion: Get coprocess output into var
Top Forums Shell Programming and Scripting Get coprocess output into var Post 302254673 by dan-e on Wednesday 5th of November 2008 12:45:18 AM
Old 11-05-2008
Question Get coprocess output into var
This is probably a simple one for the wise.

I have just started using a coprocess (first time) in order to facilitate telnet'ing from inside a shell script. It's working, but when I run a remote command I need to get the output into a local variable, but alas my kung-fu is weak.

Code:
#! /usr/bin/ksh                                        |
                                                       |
DELAY=1                                                | <= Sleep delay
UNAME=d269836                                          | <= Login credentials
PWORD=my_password                                      |
SUPWORD=su_password                                    | <= su login credentials (i know i know)
                                                       |
exec 4>&1                                              | <= Make cop output > stdout
telnet mmm2 >&4 2>&4 |&                                | <= Start cop
sleep $DELAY                                           |
print -p $UNAME                                        | <= Login
sleep $DELAY                                           |
print -p $PWORD                                        |
sleep $DELAY                                           |
print -p su -                                          | <= Go su on remote host
sleep $DELAY                                           |
print -p $SUPWORD                                      |
sleep $DELAY                                           |
print -p clear                                         | <= Clear telnet junk from screen
sleep $DELAY                                           |
print -p cO=\$\(/my_command \)\>/dev/null 2\>/dev/null | <= This *will* put the figure into $cO, but I think $cO 
sleep $DELAY                                           |    is local to the telnet session on remote host?
echo $cO                                               | <= Therefore the output from this is nothing.    
sleep $DELAY                                           |

I used the sample supplied by Perderabo to construct this (very handy, props to Perderabo!! => https://www.unix.com/shell-programming-scripting/11359-need-script-passwd-cant-use-expect-tool-3.html#post40791), and I basically understand the idea of coprocesses, but I just can't get succinct output back into a local variable. I have also tried running my_command in background (and not) followed (and preceded) by a "read -p cO" but the read just sits there and halts the script until ^C.


Any takers?
Last edited by dan-e; 11-05-2008 at 06:57 PM.. Reason: bump
 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

I/O redirection within a coprocess

Hello everybody, I have a question about I/O redirection within a coprocess. I want to setup a coprocess and then redirect output to a file on a remote machine. Here's some Perderabo code modified exec 4>&1 # # Section 1 --- Prove that we can talk with the hosts in HOSTLIST # ... (4 Replies)
Discussion started by: Mugin
4 Replies

2. Shell Programming and Scripting

Korn Shell Coprocess Performance Question

I am wracking my brains over this. I am trying to use a Korn Shell script to execute an Oracle PL/SQL procedure, using the Oracle command line interface (sqlplus). The script starts sqlplus in a coprocess, and the two processes communicate using a two-way pipe. The bgnice option is off, so both... (8 Replies)
Discussion started by: Mark Puddephat
8 Replies

3. Shell Programming and Scripting

awk - coprocess???

Hi can any one let me know if awk doesnt work with the coprocess??? I have tried a simple example mentioned below but couldnt get it working seems like awk doesnt work with the coprocess concept. I would appreciate very much for any inputs on this. exec 4>&1 awk -v count=$COUNT >&4 2>&4 |&... (6 Replies)
Discussion started by: ahmedwaseem2000
6 Replies

4. UNIX for Dummies Questions & Answers

assigning (numeric) command output to var tcsh

Hello, I'm trying to assign a numeric value that is returned from one of my programs to a variable in tcsh. I want to do: @ r10 = './my_prog file 35' where ./my_prog file 35 returns a decimal value, but this doesn't work. How do I achieve the desired result? Janet (4 Replies)
Discussion started by: psran
4 Replies

5. Shell Programming and Scripting

KSH, coprocess and SSH

Hi there, I want to connect to a Cisco router with a KSH script via coprocess: telnet 192.168.2.82|& print -p “login” print -p "password" With telnet it works. Now I want to use SSH: ssh -T -l login 192.168.2.82|& print -p "password" The router answer me I enter a bad... (7 Replies)
Discussion started by: sylvainkalache
7 Replies

6. Shell Programming and Scripting

Concatenate piped output and some var?

Hello, There is pipe chain and I want concacenate piped data with some variable: balh blah| ... $var1 What command I should use instead ... to concatenate piped output with $var1. I think I coud solve this using temp var - but could it be done in one line like sample above ? thanks... (4 Replies)
Discussion started by: vilius
4 Replies

7. Shell Programming and Scripting

SQL/Plus in a coprocess example. Also saves query results into shell variables

While assisting a forum member, I recommended running SQL/Plus in a coprocess (to make database connections and run a test script) for the duration of his script rather than starting/stopping it once for every row in a file he was processing. I recalled I made a coprocess example for folks at... (2 Replies)
Discussion started by: gary_w
2 Replies

8. Shell Programming and Scripting

Want to separate my /var/adm/messages output

Hi, Please help to seprate my /var/adm/messages output. Than i want to take this output in the excel. e,g cat /var/adm/messages Sep 4 10:16:52 ibsadm1 inetd: vnetd from 172.17.5.20 38353 Sep 4 10:16:52 ibsadm1 inetd: bpcd from 172.17.5.20 915 Sep 4 10:16:55 ibsadm1 inetd: ... (5 Replies)
Discussion started by: nirjhar17
5 Replies

9. UNIX for Advanced & Expert Users

Not logging ftp connections in /var/adm/wtmpx file (in last command output)

Hi all, I have F5 load balancer on my system and checking service status by opening an ftp session in every 30 seconds. These ftp sessions are being logged in /var/adm/wtmpx and filling up the file. when i run the last command most of the output is this ftp session. I was wondering if there is a... (1 Reply)
Discussion started by: cepxat
1 Replies

10. Shell Programming and Scripting

Nawk command to output in var

Hi I have this command, which counts number of lines in a specific file and then prints it on screen.nawk 'NF{c++}END{print "Number of GPS coordinates in file: "c}' $filename I would like to have the output put into a variable, but can't seem to find the correct argument for it. How do I... (3 Replies)
Discussion started by: bulleteyedk
3 Replies

LEARN ABOUT CENTOS

igawk

IGAWK(1)							 Utility Commands							  IGAWK(1)

NAME

       igawk - gawk with include files

SYNOPSIS

       igawk [ all gawk options ] -f program-file [ -- ] file ...
       igawk [ all gawk options ] [ -- ] program-text file ...

DESCRIPTION

       Igawk is a simple shell script that adds the ability to have ``include files'' to gawk(1).

       AWK programs for igawk are the same as for gawk, except that, in addition, you may have lines like

	      @include getopt.awk

       in your program to include the file getopt.awk from either the current directory or one of the other directories in the search path.

OPTIONS

       See gawk(1) for a full description of the AWK language and the options that gawk supports.

EXAMPLES

       cat << EOF > test.awk
       @include getopt.awk

       BEGIN {
	    while (getopt(ARGC, ARGV, "am:q") != -1)
		 ...
       }
       EOF

       igawk -f test.awk

SEE ALSO

       gawk(1)

       Effective AWK Programming, Edition 1.0, published by the Free Software Foundation, 1995.

AUTHOR

       Arnold Robbins (arnold@skeeve.com).

Free Software Foundation					    Nov 3 1999								  IGAWK(1)
All times are GMT -4. The time now is 01:29 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy