81: Notes and examples of using os.Exit(..)

Author: symonk

README.md

@@ -71,3 +71,4 @@ go run . -module closingchannels
 * [78 - Spawning Processes](spawningprocesses/main.go)
 * [79 - Execing Processes](execingprocesses/main.go)
 * [80 - Signals](signals/main.go)
+* [81 - Exit](exit/main.go)

exit/main.go

@@ -0,0 +1,17 @@
+package exit
+
+import (
+	"fmt"
+	"os"
+)
+
+// To exit a program immediately with a particular exit code
+// `os.Exit` can be used.  However it will not run defers.
+func Run() {
+	exitWithoutDefer(3)
+}
+
+func exitWithoutDefer(code int) {
+	defer func() { fmt.Println("I won't run!") }()
+	os.Exit(code)
+}

main.go

@@ -17,6 +17,7 @@ import (
 	"github.com/symonk/learning-golang/defers"
 	"github.com/symonk/learning-golang/errors"
 	"github.com/symonk/learning-golang/execingprocesses"
+	"github.com/symonk/learning-golang/exit"
 	"github.com/symonk/learning-golang/forloop"
 	"github.com/symonk/learning-golang/functions"
 	"github.com/symonk/learning-golang/generics"
@@ -133,5 +134,6 @@ func buildMap() map[string]func() {
 	fnMap["spawningprocesses"] = spawningprocesses.Run
 	fnMap["execingprocesses"] = execingprocesses.Run
 	fnMap["signals"] = signals.Run
+	fnMap["exit"] = exit.Run
 	return fnMap
 }