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How to check a variable for empty and a newline

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# 1  
Old 02-02-2010
How to check a variable for empty and a newline
I have a variable with a new line. I want to check this variable for empty or a new line

Can anyone advise
# 2  
Old 02-02-2010
Code:
if [ -z "`echo "$VARIABLE" | tr -d '\n'`" ]; then
    ...
fi

Is this what you mean?
# 3  
Old 02-02-2010
Code:
case $var in 
  ""|*"\n"*) echo hello
esac

# 4  
Old 02-03-2010
Quote:
Originally Posted by Scrutinizer
Code:
case $var in 
  ""|*"\n"*) echo hello
esac


You are testing for a literal '\n', not a newline.

Code:
NL='
'
case $var in 
  ""|*"$NL"*) echo hello
esac

# 5  
Old 02-03-2010
Oww, that's right, thanks!\n Smilie
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