pty
echo "the variable X is not the empty string"
else
echo "empty!"
fi
</code>
http://pegasus.r... n used to examine the status of a file. There are string operators and numeric comparison operators as wel... t builtin (see section 4.3 The Set Builtin).
-z string
True if the length of string is zero.
-n stringstring
True if the length of string is non-zero.
s