diff --git a/examples_test.go b/examples_test.go
index 4e64009786..dfb49e177b 100644
--- a/examples_test.go
+++ b/examples_test.go
@@ -405,7 +405,7 @@ func ExampleCommand_Run_shellComplete_zsh() {
 
 	// Simulate a zsh environment and command line arguments
 	os.Args = []string{"greet", "--generate-shell-completion"}
-	os.Setenv("0", "/usr/bin/zsh")
+	os.Setenv("SHELL", "/usr/bin/zsh")
 
 	_ = cmd.Run(context.Background(), os.Args)
 	// Output:
diff --git a/help.go b/help.go
index 626968a8f7..10c2f6e8f0 100644
--- a/help.go
+++ b/help.go
@@ -164,7 +164,7 @@ func printCommandSuggestions(commands []*Command, writer io.Writer) {
 		if command.Hidden {
 			continue
 		}
-		if strings.HasSuffix(os.Getenv("0"), "zsh") {
+		if strings.HasSuffix(os.Getenv("SHELL"), "zsh") {
 			_, _ = fmt.Fprintf(writer, "%s:%s\n", command.Name, command.Usage)
 		} else {
 			_, _ = fmt.Fprintf(writer, "%s\n", command.Name)