Screen name allow - next to letters and numbers

Add info on skipped line

.shellcheckrc

@@ -0,0 +1,2 @@
+shell=bash
+external-sources=true

Readme.md

@@ -6,11 +6,16 @@ Init screens from config files
 
 ## Config file layout
 
-```
+```txt
 <screen session name>
-<window name>#<command>
+<window name>#<command>;<command>;
+#
+;<ignored line>
 ```
 
-`screen session name` is the name you use for gstting the screen session name, see `screen -ls`. Must be Alphanumeric without spaces.
-`window name` is the name for this window
-`command` can be any comamnd sequence separated by `;`. If nothing given default `^C` shell is used
+- `screen session name` is the name you use for gstting the screen session name, see `screen -ls`. Must be Alphanumeric without spaces and cannot be empty
+- `window name` is the name for this window
+- `command` can be any comamnd sequence separated by `;`. If nothing given default `^C` shell is used
+- If there is only a `#` an empty unnamed window is opened
+- if a line starts with `;` it is skipped
+- empty lines are ignored

configs/.gitignore

@@ -0,0 +1,2 @@
+*
+!.gitignore

screen_init.sh

@@ -25,8 +25,7 @@
 set -e
 
 ERROR=0;
-if [ ! -f "$1" ];
-then
+if [ ! -f "$1" ]; then
 	echo "Cannot find screen init config file '$1'";
 	ERROR=1;
 else
@@ -35,11 +34,10 @@ else
 fi;
 
 # check if we are in a screen one, if yes, exit
-if [ -z "$STY" ];
-then
+if [ -z "$STY" ]; then
 	# check if the "work" screen exists
-	if [ ! -z "$SCREEN_NAME" ] && [[ ! -z $(screen -ls | grep ".$SCREEN_NAME\t") ]];
-	then
+	# if [ -n "$SCREEN_NAME" ] && [[ -n $(screen -ls | grep ".$SCREEN_NAME\t") ]];
+	if [ -n "$SCREEN_NAME" ] && screen -ls | grep -q ".$SCREEN_NAME\t"; then
 		echo "Screen '$SCREEN_NAME' already exists";
 		ERROR=1;
 	fi;
@@ -48,11 +46,9 @@ else
 	ERROR=1;
 fi;
 
-if [ $ERROR -eq 1 ];
-then
+if [ $ERROR -eq 1 ]; then
 	exit;
 fi;
-
 # termcap (echo $TERMCAP)
 # http://web.mit.edu/gnu/doc/html/screen_15.html#SEC89
 # in screen ^-a . to dump current termcap
@@ -79,43 +75,56 @@ export SCREENCAP="SC|screen.xterm-256color|VT 100/ANSI X3.64 virtual terminal:\
 
 # read the config file and init the screen
 pos=0;
-cat "$1" |
-while read line;
+while read -r line;
 do
-	if [ $pos -eq 0 ];
-	then
+	if [ $pos -eq 0 ]; then
 		# should I clean the title to alphanumeric? (well yes, but not now)
 		SCREEN_NAME=$line;
+		if [ -z "$SCREEN_NAME" ]; then
+			echo "[!] No screen name set";
+			exit;
+		fi;
+		if [[ ! $SCREEN_NAME =~ ^[A-Za-z0-9-]+$ ]]; then
+			echo "[!] Screen name must be alphanumeric (letters, numbers, and hyphens only): ${SCREEN_NAME}";
+			exit;
+		fi;
 		# check that we do not create double entries
 		if screen -list | grep -q "${SCREEN_NAME}"; then
-			echo "Screen with ${SCREEN_NAME} already exists";
+			echo "[!] Screen with ${SCREEN_NAME} already exists";
 			exit;
 		fi;
 	else
+		# screen number is pos - 1
+		SCREEN_POS=$(( pos-1 ));
 		# extract screen title and command (should also be cleaned for title)
 		SCREEN_TITLE=$(echo "$line" | cut -d "#" -f 1);
 		SCREEN_CMD=$(echo "$line" | cut -d "#" -f 2);
-		# screen number is pos - 1
-		SCREEN_POS=$[ $pos-1 ];
+		# skip lines that start with ";" these are comments, we do not use # as they are separators
+		if [[ $line =~ ^\; ]]; then
+			printf "[%2s] [SKIP] '%s' with command '%s'\n" $SCREEN_POS "$SCREEN_TITLE" "$SCREEN_CMD";
+			continue;
+		fi;
+		# skip empty lines
+		if [ -z "$line" ]; then
+			continue;
+		fi;
 		# for the first screen, we need to init the screen and only set title
 		# for the rest we set a new screen with title
-		if [ $pos -eq 1 ];
-		then
-			echo "Init screen with title '$SCREEN_NAME'";
+		if [ $pos -eq 1 ]; then
+			printf "===> * INIT screen with title '%s'\n" "$SCREEN_NAME";
 			screen -dmS "$SCREEN_NAME";
 			# set title for the first
 			screen -r "$SCREEN_NAME" -p $SCREEN_POS -X title "$SCREEN_TITLE";
 		else
 			screen -r "$SCREEN_NAME" -X screen -t "$SCREEN_TITLE" $SCREEN_POS;
 		fi;
-		echo "[$SCREEN_POS] Set title to '$SCREEN_TITLE'";
+		printf "[%2s] + ADD window with title '%s'\n" $SCREEN_POS "$SCREEN_TITLE";
 		# run command on it (if there is one)
-		if [ ! -z "$SCREEN_CMD" ];
-		then
-			echo "[$SCREEN_POS] Run command '$SCREEN_CMD'";
+		if [ -n "$SCREEN_CMD" ]; then
+			printf "     > RUN command '%s'\n" "$SCREEN_CMD";
 			# if ^M is garbled: in vim do: i, ^V, ENTER, ESCAPE
 			screen -r "$SCREEN_NAME" -p $SCREEN_POS -X stuff $"$SCREEN_CMD^M";
 		fi;
 	fi;
-	pos=$[ $pos+1 ];
-done;
+	pos=$(( pos+1 ));
+done <<<"$(cat "${1}")";