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Logic Explanation of Match command in Linux

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# 1  
Old 03-07-2012
Logic Explanation of Match command in Linux
I am debugging a script and have stuck up at one code line
Code:
awk -F , '{if (match($3,001)) { print $2 } }' Master20120307090511.tmp

Code:
The Master20120307090511.tmp is
 
001,ARE , 001
002,ARE , 002
003,ARE , 003
006,ARE , 006
011,ARE , 011
012,ARE , 012

What happens is when i fire this
Code:
awk -F , '{if (match($3,001)) { print $2 } }' Master20120307090511.tmp
 
it outputs me as 
ARE
ARE
ARE

But if this command is fired
Code:
awk -F , '{if (match($3,011)) { print $2 } }' Master20120307090511.tmp
it returns me blank

I was wondering if 011 exists in the Master file then y does it return me blank

Could you all please help me in understanding this logic.

Thanks
# 2  
Old 03-07-2012
The reason for three matches to the first is that an unquoted integer in awk begining with zero is read as an octal number, thus 1 => 1 which occurs in three records and 11 => 9 (which isn't present).

try quoting instead to avoid this awk -F , '{if (match($3,"011")) { print $2 } }'
This User Gave Thanks to Skrynesaver For This Post:
vee_789
# 3  
Old 03-07-2012
I would have never known this thanks a lot.
# 4  
Old 03-07-2012
This behavior seems to be gawk-only. The other awks I tried display ARE just fine without quotes.
If I use
Code:
awk --posix -F, '$3~011{ print $2 }' file

or
Code:
awk --posix -F , '{if (match($3,011)) { print $2 } }'

then ARE is displayed as well..

Perhaps we should introduce a standard banner on this forum:
if on Solaris use /usr/xpg4/bin/awk. When using gawk, use (g)awk --posix
Last edited by Scrutinizer; 03-07-2012 at 08:44 AM..
This User Gave Thanks to Scrutinizer For This Post:
Skrynesaver
# 5  
Old 03-07-2012
Hi Skrynesaver

So now if i have
Code:
awk -F , '{if (match($3,014)) { print $2 } }' Master20120307090511.tmp
The decimal is 33

But 33 does not exists in the master file still it returns me

ARE

Is it because it considers only the number 3

Thanks
# 6  
Old 03-07-2012
014 octal = 12 decimal and there does appear to be a row with a 12 in $3 in the sample data provided...
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