Make tests of tempdir var more explicit

I'm pretty sure I've seen at least one implementation of sh(1) upset
about [ "$var" ] over [ -n "$var" ]

1 files changed, 1 insertions, 1 deletions

diff --git a/bin/urlc b/bin/urlc
index 351d8623..b898b99c 100755
--- a/bin/urlc
+++ b/bin/urlc
@@ -9,7 +9,7 @@ tm=${URLCHECK_TIMEOUT:-8}
 # exit
 td=
 cleanup() {
-    [ "$td" ] && rm -fr -- "$td"
+    [ -n "$td" ] && rm -fr -- "$td"
     if [ "$1" != EXIT ] ; then
         trap - "$1"
         kill "-$1" "$$"