devdraw: cleanup, fix macargv

mac/Plumb.app/Contents/MacOS/plumb

@@ -1,12 +1,21 @@
 #!/bin/bash
+
 . ~/.bashrc
 PLAN9=${PLAN9:-/usr/local/plan9}
-filename="$($PLAN9/bin/macargv)"
-# Blank are problematic in the file name.  Make them go away but keep the content.
-if echo "$filename" | grep -q " "
-then
-	base=$(basename "$filename" | sed 's/ /_/g')
-	cat "$filename" | plumb -i -d edit -a "action=showdata filename=/BadName/$base"
-else
-	$PLAN9/bin/plumb -d edit "$filename"
-fi
+
+bin=$PLAN9/bin
+IFS=$'\n'
+
+for file in $($bin/macargv)
+do
+	# Blanks are problematic in filenames: just plumb
+	# the file's content.
+	if echo "$file" | grep -q " "
+	then
+		base=$(basename "$file" | sed 's/ /_/g')
+		attr="action=showdata filename=/BadName/$base"
+		cat $file | "$bin/plumb" -i -d edit -a "$attr"
+	else
+		"$bin/plumb" -d edit "$file"
+	fi
+done