Allow inline countdown.

README.md

@@ -1,20 +1,9 @@
 # CountDown.sh
+
 A simple script to countdown from a certain number to zero. I made it so that
 I can easily delay the playing time of songs by a few seconds before I play it
 on the guitar.
 
-```
-USAGE:
-	countdown.sh <sec>
-
-OPTIONS:
-	<sec>      number to countdown from [default: 5]
-
-EXAMPLE:
-	Countdown from 7 and then play Scott Stapp's "Last Hallelujah"
-		./countdown 7 ; mpv 12_-_Last_Hallelujah.flac
-```
-
 ## License
 
 This project is licensed under the terms & conditions of the ZLib license.

countdown.sh

@@ -22,17 +22,48 @@
 # 3. This notice may not be removed or altered from any source
 #    distribution.
 
-if [ -z $1 ]
+set -euo pipefail
+
+INLINE=0
+COUNT=5
+
+if [ $# -ge 1 ] && [ $# -le 2 ]
 then
-	COUNT=5
-else
-	COUNT=$1
+	for arg in "$@"
+	do
+		if [ "$arg" = "-i" ]
+		then
+			INLINE=1
+		elif [ "$arg" = "-h" ] || [ "$arg" = "--help" ]
+		then
+			echo "Usage: $0 [-i] [COUNT]"
+			echo "  COUNT: Number of seconds to count down from (default: 5)"
+			echo "  -i: Inline mode (do not print each number on a new line)"
+			exit 0
+		elif [[ "$arg" =~ [0-9]+ ]]
+		then
+			COUNT="$arg"
+		else
+			echo "Unknown argument: $arg"
+			exit 1
+		fi
+	done
 fi
 
-for i in $(seq $COUNT -1 1)
+for i in $(seq "$COUNT" -1 1)
 do
-	echo $i
+	if [ $INLINE -eq 0 ]
+	then
+		echo "$i"
+	else
+		printf "\r%s" "$i"
+	fi
 	sleep 1
 done
 
-echo 0
+if [ $INLINE -eq 0 ]
+then
+	echo "0"
+else
+	printf "\r%s\n" "0"
+fi