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difference between NULL and ' '


 
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# 1  
Old 04-04-2002
Error difference between NULL and ' '

If I write a ksh script like :
if [ ($2 = ' ' ) ] || [ ( $3 = ' ' ) ] exit
fi

because I want to control the command syntax.
Do I use ' ' or NULL to specify the none value of the arguments
in the command.

thanks ....
# 2  
Old 04-04-2002
I may be incorrect, but you should be able to use:
if [ "$1" = "" ]; then ...

Another way I've seen it done is like this:
if [ X"$1" = "X" ]; then ...

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