Unix script using awk

Question

I have a problem and I dont know why my code doesn't work
the code:

prot="abc"
awk '{
if ( $1 == $prot )
     print $2
}' file.txt

but when I change my code to this it works as it was intented to work

awk '{
if ( $1 == "abc" )
     print $2
}' file.txt

Why is that happening?

P.P · Accepted Answer · 2014-05-09 12:08:03Z

2

You cannot use a bash variable directly into your script.

Instead, give it with the -v option:

-v prot="$prot"

All together:

prot="abc"
awk -v prot="$prot" '{
if ( $1 == prot )
     print $2
}' file.txt

P.P

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answered May 9, 2014 at 12:01

fedorqui

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2 Comments

+1.. but please fix the all together code block.. :-)

I get improper assignment -v prot="$prot"{..

Jotne · Accepted Answer · 2014-05-09 12:31:09Z

0

Here is an other variation:

prot="abc"
awk '{
if ( $1 == prot )
     print $2
}' prot="$prot" file.txt

answered May 9, 2014 at 12:31

Jotne

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