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simple wc problem

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# 1  
Old 12-05-2011
simple wc problem
Hi there, Im sure there is a simple explanation for this but I have a file like this with no balnk lines


Code:
 
peter
paul
john

I run the command

Code:
 
# var=`grep paul file.txt`
# echo $var
paul
# echo $var | wc -l
    1

but when I grep for a value that isnt in the file, i still get the same line count because it returns a blank line

Code:
 
# var=`grep steve file.txt`
# echo $var
 
# echo $var | wc -l
    1

Does anybody know why this happens?
# 2  
Old 12-05-2011
echo $var when $var is empty is equivalent to just echo - which prints a blank line...
# 3  
Old 12-05-2011
And if you counted in words, you would have seen 0:
Code:
an12:/home/vbe $ echo $var|wc -w
       0

# 4  
Old 12-05-2011
The command "wc -l" counts the number of line terminators (line feed characters). In your script the "echo" created the line terminator in both cases.

Maybe try "test -z".
Code:
if [ -z "${var}" ]
then
        echo "The variable called var is empty"
fi

# 5  
Old 12-05-2011
ok thanks, ill use wc -w instead
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