fixes

src/app.rs

@@ -94,7 +94,7 @@ impl AppOption {
                 "--close-from n | -C n",
                 "Close all file descriptors greater than or equal to n.",
             ),
-            AppOption::GenerateConfig => ("--gen-config", "Print example config to standard output."),
+            AppOption::GenerateConfig => ("--gen-conf", "Print example config to standard output."),
             AppOption::Group => (
                 "--group | -g",
                 "Run the command with the primary group set to group.",

src/main.rs

@@ -81,7 +81,14 @@ pub fn execute(app: App) -> Result<(), String> {
             cmd.env("HOME", home_dir);
         }
         // execute the child
-        let mut child = cmd.spawn().unwrap();
+        let mut child = if let Ok(child) = cmd.spawn() {
+            child
+        } else {
+            return Err(format![
+                "Error: {}: Command not found.",
+                args.first().unwrap()
+            ]);
+        };
         if app.background {
             std::process::exit(0);
         } else {