diff --git a/diff-deb-new.sh b/diff-deb-new.sh
index 6d6c8b3..0424e01 100755
--- a/diff-deb-new.sh
+++ b/diff-deb-new.sh
@@ -1,6 +1,6 @@
 #!/bin/sh
 # Usage: diff-deb-new.sh right.deb
-right=$1.contents
+right=$(mktemp /tmp/diff-deb.XXXXXX)
 dpkg --contents $1 | awk '!($2=$3=$4=$5="")' > $right
 touch -m -d "1980-01-01" $right
 
diff --git a/diff-deb.sh b/diff-deb.sh
index 7054545..6164b93 100755
--- a/diff-deb.sh
+++ b/diff-deb.sh
@@ -1,10 +1,10 @@
 #!/bin/sh
 # Usage: diff-deb.sh left.deb right.deb
-left=$1.contents
+left=$(mktemp /tmp/diff-deb.XXXXXX)
 dpkg --contents $1 | awk '!($2=$3=$4=$5="")' > $left
 touch -m -d "1980-01-01" $left
 
-right=$2.contents
+right=$(mktemp /tmp/diff-deb.XXXXXX)
 dpkg --contents $2 | awk '!($2=$3=$4=$5="")' > $right
 touch -m -d "1980-01-01" $right