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Passing eval value to a variable


 
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# 1  
Passing eval value to a variable

Hello,

I have a script that does an scp to a server and then gets the number of process running on that server, the o/P should be stored in a variable for further processing

Code:
eval `echo "ssh -q $Infa_user@$host 'csh -c $CMD '"`
where
CMD="ps -ef | grep -i ${INFA_REPO} | grep -v grep | wc -l"

the eval command works fine in the script and o/P the no of processes however when i put it a variable, i get an errror i.e

Code:
STATUS=`eval `echo "ssh -q $Infa_user@$host 'csh -c $CMD '"``

results in error : not found [No such file or directory.

Any idea's how to do that ?
# 2  
i found it

status=`eval "eval "echo "ssh -q $Infa_user@$host 'csh -c $CMD '"""`

works fine.
# 3  
Too many layers

No need for all the extra layers. On my machine, the following does the same thing:

Code:
$ cmd1="ps -efwww | grep sbin"
$ cmd2="bash -c '$cmd1'"
$ results=$(ssh -q myhost "$cmd2")

or simply

Code:
$ results=$(ssh -q myhost "$cmd1")

eval has its uses, but only at the Ph.D level Smilie

Last edited by vbe; 04-29-2009 at 05:37 AM.. Reason: removed faulty URL (for approval...)

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