diff --git a/lib/bash/parse_options.sh b/lib/bash/parse_options.sh
index 18e66412..9eaccb06 100644
--- a/lib/bash/parse_options.sh
+++ b/lib/bash/parse_options.sh
@@ -26,9 +26,9 @@ set -u
 
 # Global variables.  These must be global because declare inside a
 # sub will be scoped locally.
-declare -a ARGV      # non-option args (probably input files)
-declare EXT_ARGV     # everything after -- (args for an external command)
-declare -a OPT_ERRS  # errors while parsing options, for usage_or_errors()
+declare -a ARGV     # non-option args (probably input files)
+EXT_ARGV=""         # everything after -- (args for an external command)
+declare -a OPT_ERRS # errors while parsing options, for usage_or_errors()
 OPT_VERSION="no"
 OPT_HELP="no"
 
diff --git a/lib/bash/tmpdir.sh b/lib/bash/tmpdir.sh
index 6349bf02..d1b9e1b7 100644
--- a/lib/bash/tmpdir.sh
+++ b/lib/bash/tmpdir.sh
@@ -25,22 +25,23 @@ set -u
 
 # Global variables.
 TMPDIR=""
-OPT_TMPDIR=${OPT_TMPDIR:""}
 
 # Sub: mk_tmpdir
 #   Create a secure tmpdir and set TMPDIR.
 #
-# Optional Global Variables:
-#   OPT_TMPDIR - User-specified --tmpdir (default none).
+# Optional Arguments:
+#   dir - User-specified tmpdir (default none).
 #
 # Set Global Variables:
 #   TMPDIR - Absolute path of secure temp directory.
 mk_tmpdir() {
-   if [ -n "$OPT_TMPDIR" ]; then
-      TMPDIR="$OPT_TMPDIR"
-      if [ ! -d "$TMPDIR" ]; then
-         mkdir $TMPDIR || die "Cannot make $TMPDIR"
+   local dir=${1:-""}
+
+   if [ -n "$dir" ]; then
+      if [ ! -d "$dir" ]; then
+         mkdir $dir || die "Cannot make tmpdir $dir"
       fi
+      TMPDIR="$dir"
    else
       local tool=`basename $0`
       local pid="$$"
diff --git a/t/lib/bash/tmpdir.sh b/t/lib/bash/tmpdir.sh
index a5b86823..55098f4d 100644
--- a/t/lib/bash/tmpdir.sh
+++ b/t/lib/bash/tmpdir.sh
@@ -17,19 +17,25 @@ cmd_ok "test ! -d $tmpdir" "rm_tmpdir"
 
 is "$TMPDIR" "" "rm_tmpdir resets TMPDIR"
 
-# --tmpdir
-OPT_TMPDIR="/tmp/use--tmpdir"
+# ###########################################################################
+# User-specified tmpdir.
+# ###########################################################################
+
+local dir="/tmp/use--tmpdir"
 
 is "$TMPDIR" "" "TMPDIR not defined"
 
-cmd_ok "test ! -d $OPT_TMPDIR" "--tmpdir does not exist yet"
+cmd_ok "test ! -d $dir" "--tmpdir does not exist yet"
 
-mk_tmpdir
-is "$TMPDIR" "/tmp/use--tmpdir" "mk_tmpdir uses --tmpdir"
+mk_tmpdir $dir
+is "$TMPDIR" "$dir" "mk_tmpdir uses --tmpdir"
 
-cmd_ok "test -d $TMPDIR" "mk_tmpdir creates --tmpdir"
-
-tmpdir=$TMPDIR;
+cmd_ok "test -d $dir" "mk_tmpdir creates --tmpdir"
 
 rm_tmpdir
+
 cmd_ok "test ! -d $tmpdir" "rm_tmpdir removes --tmpdir"
+
+# ###########################################################################
+# Done
+# ###########################################################################