Added an error if the output file already exists.

nyan

@@ -43,7 +43,13 @@ if [ -z "$output_file" ]; then
 	exit 1
 fi
 
-echo "Concatenating files..."
+# TODO: Add overwrite switch.
+if [ -e "$output_file" ]; then
+	echo "Error: Output file exists."
+	exit 1
+fi
+
+echo "Preparing to concatenate files."
 declare -i total_size=0
 for fname in "$@"; do
 	if [ ! -e "$fname" ]; then
@@ -59,8 +65,7 @@ for fname in "$@"; do
 	fi
 done
 
-# TODO: Make sure that output_file does not exist. Maybe add an overwrite switch.
+echo "Concatenating files..."
-
 if [ $abort -eq 0 ]; then
 	cat "$@" | pv -epts "$total_size" > "$output_file"
 	echo "Done!"