add version to help

meson.build

@@ -3,7 +3,8 @@ project('diya-session-manager',
     version: '0.1.1',
     license: 'MIT',
     meson_version: '>=0.58.0',
-    default_options: ['c_std=gnu11', 'warning_level=3'])
+    default_options: ['c_std=gnu11', 'warning_level=3']
+)
 
 lib_so_version = '0'
 
@@ -17,6 +18,7 @@ add_project_arguments(
         '-Wno-pedantic',
         '-Werror=implicit-function-declaration',
         '-Werror=return-type',
+        '-DVERSION="@0@"'.format(meson.project_version())
     ],
     language: 'c')
 

src/main.c

@@ -16,7 +16,11 @@ static gchar **g_shell_argv;
 
 static void help(const char* name)
 {
+    printf("diya-session-manager - a session manager for diya shells\n");
     printf("Usage: %s [-c config_file]\n" ,name);
+#ifdef VERSION
+    printf("Version: %s\n", VERSION);
+#endif
 }
 
 static gboolean restart(gpointer d)