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Eval command help

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# 1  
Old 11-16-2010
Eval command help
I have file called myfile which has the text "myserver" in it. I need to have a command to ping "myserver". How would I do that?

I tried
Quote:
myvar= 'cat myfile'
when I type
Quote:
"eval $myvar"
at the terminal I get the output as
Quote:
"myserver"
. How do I do something like a
Quote:
ping "eval $myvar"
?

thanks,
Nick
# 2  
Old 11-16-2010
One way (no eval needed):

Code:
cat myfile | while read server_name
do
       ping "${server_name}"
done

This User Gave Thanks to methyl For This Post:
nikhilfake
# 3  
Old 11-16-2010
If myserver is the only word in myfile
Code:
 
ping $(cat myfile)

This User Gave Thanks to anurag.singh For This Post:
nikhilfake
# 4  
Old 11-16-2010
Code:
myvar=$(< myfile)
ping $myvar

or:
Code:
ping "$(< myfile)"

This User Gave Thanks to Franklin52 For This Post:
nikhilfake
# 5  
Old 11-16-2010
Quote:
Originally Posted by anurag.singh
If myserver is the only word in myfile
Code:
 
ping $(cat myfile)

Actually, myserver is not the only word. It is in a line called
Quote:
Server-Name=myserver
So I used
Code:
ping $(cat myfile | grep "Server-Name" | cut -d'=' -f2)

thanks guys!!!
Last edited by nikhilfake; 11-16-2010 at 01:53 PM..
# 6  
Old 11-16-2010
Quote:
Originally Posted by nikhilfake
Actually, myserver is not the only word. It is in a line called


So I used
Code:
ping $(cat myfile | grep "Server-Name" | cut -d'=' -f2)

thanks guys!!!
Code:
myvar=$(< myfile)
ping ${myvar#*=}

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