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usage of underscore in awk

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# 1  
Old 12-08-2008
usage of underscore in awk
Hi what is the purpose of using underscore in awk. I suppose it is for defining macro's and reducing repeatation but can some one show me an example?
# 2  
Old 12-08-2008
Could you give an example? I suppose it's a simple variable name without any special meaning (not like in Perl, for example).
# 3  
Old 12-08-2008
here is the example i found in one of the posts and there are many more similar posts.

Code:
awk -v ID=$ID '$NF==ID{_=1} !NF && _{exit}_'  file > request_id_data.txt

# 4  
Old 12-08-2008
It's an ordinary AWK variable, it's the same as:

Code:
awk -v ID=$ID '$NF==ID{myvar=1} !NF && myvar{exit}myvar'

As far as my posts are concerned (the above is not mine, it's from danmero's post I think), it's just an attempt to make a boring code look nicer (like Apollinaire's poetrySmilie).
Last edited by radoulov; 12-08-2008 at 07:16 AM..
# 5  
Old 12-08-2008
Sorry Its not a relevant question. I have gone a bit lousy to read the posts properly.
Last edited by ahmedwaseem2000; 12-08-2008 at 07:09 AM..
# 6  
Old 12-08-2008
1 or 0 (true or false in boolean context) as far as the above example is concerned.
# 7  
Old 12-08-2008
radoulov -Thanks for your replies
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