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awk system() prints extra 0 -- why?

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# 1  
Old 03-12-2010
awk system() prints extra 0 -- why?
Here's the command I'm running:

Code:
# echo "hi" | awk '{etime = system("hostname") ; close("hostname") ; print etime""}'

And here's the ouput:

Code:
server.domain.tld
0

Why in the world is that second line, the one that's just "0", there? Many thanks in advance.
# 2  
Old 03-12-2010
'man nawk' yields:
Code:
     system(expression)
           Execute the command given by expression  in  a  manner
           equivalent  to  the system(3C) function and return the
           exit status of the command.

Your '0' is the exit code of the exec-ed 'command'.
Code:
echo "hi" | awk '{cmd="hostname"; cmd | getline etime; close(cmd) ; print etime}'

# 3  
Old 03-12-2010
Ah, thanks for the reply. Somehow I missed that. The awk (not [m/n/g/h]awk) man page makes a similar statement that I somehow managed to completely overlook. Thanks for the clever solution as well. Well, clever to me, anyway... I'm sure it's second nature to you folks that actually know this stuff...
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