[CALUG] Shell script question.
bdebelius at intelesyscorp.com
Wed Mar 3 14:05:57 EST 2010
Looking at Bacula scripts and other scripts, I see a test for an
empty string performed by adding an 'x' before the variable, and then
comparing this to another string that is just an 'x'.
The shell test function has a -z string test that returns true if the
string is empty.
It appears to me that more people use the 'x' comparison. Is there a
technical reason why one would be preferable to the other?
Why would you do this:
if [ "x$var" = "x" ]; then
Instead of this:
if [ -z $var ]; then
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