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test command looks strange...

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# 1  
Old 11-02-2007
test command looks strange...
I just ran into this today, and don't know what to make of it...
Code:
if test x$SERVER = x
then
        echo $USAGE
        exit 1
fi

I know what everything in there does, except for the 'x' jazz...
# 2  
Old 11-02-2007
Quote:
Originally Posted by jjinno
I just ran into this today, and don't know what to make of it...
Code:
if test x$SERVER = x
then
        echo $USAGE
        exit 1
fi

I know what everything in there does, except for the 'x' jazz...
It is effecitvely doing

Code:
if test "$SERVER" = ""
then
     ....

rather than using quotes, it prefixes an x to the string to ensure it's not an empty string argument. Where it falls down of course is if there is a space in $SERVER.
# 3  
Old 11-02-2007
hahahaha... of course, the obvious answer escapes me.

I didn't even think of it as concatenation till you mentioned that.

Thank you
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