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Nawk sub not substituting

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# 1  
Old 06-12-2014
Nawk sub not substituting
I am trying to use nawk sub to substitute a string in a file. Both the pattern and the replacement I set as variables using bash.

here is the code:
Code:
#!/bin/bash -x
ydate=`/usr/local/bin/date +%Y%m%d`
echo $ydate
test_ca=/home/mdadmin/test_ca
for i in `cat ${test_ca}`
do
if [[ $i == *cana* ]]; then
new_f=`/usr/bin/nawk -F"/" -v dt="$ydate" '{ print $5 "." dt }' $test_ca`
echo $new_f
nawk -F "/" -v y=$i,z=$new_f ' { sub(y,z,$4) ; print $0} ' ${test_ca}
fi
done

When I execute it returns
Code:
/pub/data/cana/Peoccam

I want it to return :
Code:
/pub/data/cana/Peoccam.20140612

Any suggestions are greatly appreciated. I have the bash -x output if needed.
# 2  
Old 06-12-2014
There seems to be a bit of overhead. Why are you processing each line in test_ca then running nawk against it twice. The idea behind nawk is it's a filtering language so you should only have to filter your input file once.

Simplify this and create a nawk file and use the -f option to point to it.

Post your input file test_ca.
# 3  
Old 06-12-2014
I need to execute an mv on the file to rename with the date appended. I removed the mv command from the post for simplicity.

So bascially I need to rename the file and then change the name in the test_ca file so I can sftp it.

here are the contents of test_ca -

Code:
/pub/data/cana/Peoccam

# 4  
Old 06-12-2014
Not quite sure what your requirements are without seeing an example input file and output file, but this might get you along the way:

Code:
nawk -F/ -v dt=$(/usr/local/bin/date +%Y%m%d) '
/cana/ { v=$5"."dt}
{ $NF=v ; print } ' OFS=/ /home/mdadmin/test_ca


... or even. Remove echo (in read) once your sure it's going to do what you want:

Code:
while read filename
do
    echo mv $filename $filename.$(/usr/local/bin/data +%Y%m%d)
done < /home/mdadmin/test_ca

Last edited by Chubler_XL; 06-12-2014 at 05:04 PM..
This User Gave Thanks to Chubler_XL For This Post:
smenago
# 5  
Old 06-13-2014
Thanks. Seeing a different approach does help.

However, do you have any ideas why the sub is not substituing. In the original piece of code I did the following-

Code:
nawk -F "/" -v y=$i,z=$new_f ' { sub(y,z,$4) ; print $0} ' ${test_ca}

The Z is -
Code:
/pub/data/cana/Peoccam.20140612

the y is

Code:
/pub/data/cana/Peoccam

this is the output from shell-
Code:
smenago@ftp02$ bash -x test_app
++ /usr/local/bin/date +%Y%m%d
+ ydate=20140612
+ echo 20140612
20140612
+ test_ca=/home/mdadmin/test_ca
++ cat /home/mdadmin/test_ca
+ for i in '`cat ${test_ca}`'
+ [[ /pub/data/cana/Peoccam == *cana* ]]
++ /usr/bin/nawk -F/ -v dt=20140612 '{ print $5 "." dt }' /home/mdadmin/test_ca
+ new_f=Peoccam.20140612
+ echo Peoccam.20140612
Peoccam.20140612
+ mv /pub/data/cana/Peoccam /pub/data/cana/Peoccam.20140612
mv: cannot access /pub/data/cana/Peoccam
+ nawk -F / -v y=/pub/data/cana/Peoccam,z=Peoccam.20140612 ' { sub(y,z,$4) ; print $0} ' /home/mdadmin/test_ca
/pub/data/cana/Peoccam

Last edited by Scrutinizer; 06-13-2014 at 12:13 PM.. Reason: Additional code tags
# 6  
Old 06-13-2014
Quote:
Originally Posted by smenago
Thanks. Seeing a different approach does help.

However, do you have any ideas why the sub is not substituing. In the original piece of code I did the following-

nawk -F "/" -v y=$i,z=$new_f ' { sub(y,z,$4) ; print $0} ' ${test_ca}
The Z is -
/pub/data/cana/Peoccam.20140612

the y is

/pub/data/cana/Peoccam
this is the output from shell-
Code:
smenago@ftp02$ bash -x test_app
++ /usr/local/bin/date +%Y%m%d
+ ydate=20140612
+ echo 20140612
20140612
+ test_ca=/home/mdadmin/test_ca
++ cat /home/mdadmin/test_ca
+ for i in '`cat ${test_ca}`'
+ [[ /pub/data/cana/Peoccam == *cana* ]]
++ /usr/bin/nawk -F/ -v dt=20140612 '{ print $5 "." dt }' /home/mdadmin/test_ca
+ new_f=Peoccam.20140612
+ echo Peoccam.20140612
Peoccam.20140612
+ mv /pub/data/cana/Peoccam /pub/data/cana/Peoccam.20140612
mv: cannot access /pub/data/cana/Peoccam
+ nawk -F / -v y=/pub/data/cana/Peoccam,z=Peoccam.20140612 ' { sub(y,z,$4) ; print $0} ' /home/mdadmin/test_ca
/pub/data/cana/Peoccam

Looks like variable you properly not defined

see difference here in example :

Code:
$ awk -vx=1,y=2 'BEGIN{print y}'

$ awk -vx=1,y=2 'BEGIN{print x}'
1,y=2

$ awk -vx=1 -vy=2 'BEGIN{print x,y}'
1 2

This User Gave Thanks to Akshay Hegde For This Post:
smenago
# 7  
Old 06-13-2014
Also even if you get y and z assigned properly, lets expand out what sub(y,z,$4) is seeing:

Code:
sub("/pub/data/cana/Peoccam", "Peoccam.20140612",  "cana")

So substitute "/pub/data/cana/Peoccam" with "Peoccam.20140612" in string "cana"
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