diff --color -u a/Makefile b/Makefile
--- a/Makefile	2014-06-16 03:27:59
+++ b/Makefile	2023-01-15 03:32:37
@@ -8,6 +8,9 @@
 
 CC=gcc
 CFLAGS=-O
+TEA_VERSION?= "0.0.0-dev"
 
 sl: sl.c sl.h
+	sed -i.bak -e "s/#define TEA_VERSION \".*\"/#define TEA_VERSION \"$(TEA_VERSION)\"/" sl.h
+	rm sl.h.bak
 	$(CC) $(CFLAGS) -o sl sl.c -lncurses
Common subdirectories: a/props and b/props
diff --color -u a/sl.c b/sl.c
--- a/sl.c	2014-06-16 03:27:59
+++ b/sl.c	2023-01-15 03:27:18
@@ -39,6 +39,8 @@
 #include <curses.h>
 #include <signal.h>
 #include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
 #include "sl.h"
 
 void add_smoke(int y, int x);
@@ -73,6 +75,10 @@
             case 'F': FLY      = 1; break;
             case 'l': LOGO     = 1; break;
             case 'c': C51      = 1; break;
+            case 'v':
+                printf("sl version %s", TEA_VERSION);
+                exit(0);
+                break;
             default:                break;
         }
     }
diff --color -u a/sl.h b/sl.h
--- a/sl.h	2014-06-16 03:27:59
+++ b/sl.h	2023-01-15 03:33:08
@@ -12,6 +12,8 @@
 #define D51LENGTH	83
 #define D51PATTERNS	 6
 
+#define TEA_VERSION "UNSET"
+
 
 #define D51STR1  "      ====        ________                ___________ "
 #define D51STR2  "  _D _|  |_______/        \\__I_I_____===__|_________| "