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awk print last line returns empty string

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# 1  
Old 03-14-2011
awk print last line returns empty string
hello

I have a file with lines of info separated with "|"

I want to amend the second field of the last line, using AWK
my problem is with geting awk to return the last line

this is what I am using

Code:
 
awk  'END{ print  $0 }' myFile

but I get an empty result

I tried the same thing with tail
Code:
 
tail -1 myFile

which works fine and returns the last line, however I need it to work with awk

Also tried print, print $1, print $* with no luck,

any suggestion would be much appriciated!

---------- Post updated at 03:59 PM ---------- Previous update was at 03:53 PM ----------

This is what I get

Code:
 
$ tail -1 myFile 
251|21|FOOTER|FILE||22
$ awk 'END{print}' myFile
 
$

# 2  
Old 03-14-2011
Code:
awk '{x=$0}END{print x}' myFile

or
Code:
sed '$!d' myFile

or
Code:
sed -n '$p' myFile

or
Code:
tail -1 myFile

# 3  
Old 03-14-2011
Quote:
Originally Posted by ctsgnb
Code:
awk '{x=$0}END{print x}' myFile

I think it should be written like below:

Code:
awk -F"|" '{x=$0}END{print x}' myFile

# 4  
Old 03-14-2011
Quote:
Originally Posted by ahmad.diab
I think it should be written like below:

Code:
awk -F"|" '{x=$0}END{print x}' myFile

Ooops ... i was focusing on getting the last line Smilie

Code:
nawk -F\| '{$2="something_else_modified";x=$0}END{print x}' OFS=\| infile

Last edited by ctsgnb; 03-14-2011 at 01:41 PM..
# 5  
Old 03-14-2011
Sadly the awk way still returns empty
so i tried this:

Code:
 
var1=$(cat myFile | wc -l)
echo $var1
 
awk -F"|" '$1==var1 {$2=0; print >> "myFile"}' OFS="|" myFile

now I know that I cannot just use $ to pass shell variables into awk, and the above does not work, how can I pass var1 into the awk?
ideally this what I want to do, "on the last line, change the second field to 0"
# 6  
Old 03-14-2011
Code:
awk -F\| 'END{print $2}' file

Smilie

---------- Post updated at 12:43 PM ---------- Previous update was at 12:41 PM ----------

Code:
var=VAR
awk -F\| -vv=$var 'END{print $2, v}' file

# 7  
Old 03-14-2011
Quote:
Originally Posted by danmero
Code:
awk -F\| 'END{print $2}' file

Smilie

---------- Post updated at 12:43 PM ---------- Previous update was at 12:41 PM ----------

Code:
var=VAR
awk -F\| -vv=$var 'END{print $2, v}' file


you got me very confused here...

this what I tried after your reply:

Code:
 
var1=$(cat myFile| wc -l)
echo $var1
 
awk -F"|" -v v="$var1" ' $1=v {$2=0; print >> "myFile"}' myFile

I dont just want to print the second field of the last line, I want to change it to 0, my problem is END does not work as for some reason it thinks the last line is empty

now what it does is changing everything to 0 infinetly...
Last edited by TasosARISFC; 03-14-2011 at 02:16 PM.. Reason: more info
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