Please help me out: I've seen this construct
several times, like in scrutinizer's today's post
but I can't find (manuals, man pages, internet FAQs,...) an explanation of what it does resp. stands for. Any hint is appreciated!
Awk's basic syntax is <expression> {<code-block>}. If expression evaluates to true, the associated block is executed. Either may be omitted; if the expression is omitted, true is assumed, and if the code block is omitted "print" is assumed. 1 evaluates as the expression to true, and so the single 1 imples 1 { print }.
---------- Post updated at 10:42 ---------- Previous update was at 10:37 ----------
Looking at the example you gave, this is how I would have written it:
It might be easier to see the difference if not smashed all on one line:
Last edited by agama; 07-28-2012 at 11:44 AM..
Reason: typo
I would put forward though that leaving out the default action {print $0} is no more a short-cut than leaving out the default condition 1, and also print prints the default value, which is $0 (and the semicolons are unnecessary). So in full it would be..
Which can of course be combined into 1 block, since the condition is the same (like agama did in post #2)..
I sometimes have a preference for one-liners because I think they are sometimes easier to read (but only if they are short, true one-liners (fewer than 65 characters), and they are great for cutting and pasting or just composing on the command line..
Last edited by Scrutinizer; 07-28-2012 at 06:17 PM..
Thanks to both of you. I regarded the {...} in front of the 1 to be the <action block> so the lonely 1 fooled me. Adding "; print" to the "action block" would have done the task as well, I see now. "always learning" as agama states!
Hi all,
I thought this would be simple, but I've been having a lot of trouble trying to write this IF statement, if I may ask for help pls:
In BASH, how would I construct the if statement:
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O/P
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Path:1
------
/home/data/test/run/
Path:2
------
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