lean into examples

examples/exit/exit.go

@@ -0,0 +1,22 @@
+// Use `os.Exit` to immediatly exit with a given
+// status.
+
+package main
+
+import "os"
+
+func main() {
+    // `defer`s will _not_ be run when using `os.Exit`, so
+    // this `println` will never be called.
+    defer println("!")
+
+    // Exit with status 3.
+    os.Exit(3)
+}
+
+// Note that unlike e.g. C, Go does not use an integer
+// return value from `main` to indicate exit status. If
+// you'd like to exit with a non-zero status you should
+// use `os.Exit`.
+
+// todo: discuss building before getting here

examples/exit/exit.sh

@@ -0,0 +1,13 @@
+#  If you run `exit.go` using `go run`, the exit
+# will be picked up by `go` and printed.
+$ go run exit.go
+exit status 3
+
+# By building and executing a binary you can see
+# the status in the terminal.
+$ go build exit.go
+$ ./exit
+$ echo $?
+3
+
+# Note that the `!` from our program never got printed.