How do you check if a variable has been assigned?


 
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# 1  
Old 12-04-2011
How do you check if a variable has been assigned?

I am trying to check whether a variable has been assigned on the command line or not.

Here is what I did:
Code:
#!/usr/bin/bash

if( $variable  == '\0')
{
print "variable  was not assigned"
exit
}
else
NF = 2 {print $1, "[LABEL=" $2 "]"}
exit 
fi

awk -f question1.awk variable = 58 letters.txt.

So basically, its meant to check if variable has been assigned to any value if its not assigned, halt. If it is, then go ahead and print the fields in the file letters.txt. Please help me!

Last edited by radoulov; 12-04-2011 at 12:28 PM.. Reason: Code tags!
# 2  
Old 12-04-2011
Why is this suspiciously like:

https://www.unix.com/unix-dummies-que...esnt-work.html

??
# 3  
Old 12-04-2011
Because I forgot my password...and I didnt think to just click on the forgot password link. Please i do need help though>
# 4  
Old 12-04-2011
I don't see any point in helping you, if you still think NF = 2 is correct, and you don't appear to have accepted anything from the other thread.
 
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