Ensure libmutton.ini is created with 0600 permissions (on *nix)

core/configParser.go

@@ -92,6 +92,7 @@ func WriteConfig(valuesToWrite [][3]string, keysToPrune [][2]string, append bool
 	}
 
 	// save to libmutton.ini
+	setUmask(0077) // only give permissions to owner
 	err := cfg.SaveTo(global.ConfigPath)
 	if err != nil {
 		back.PrintError("Failed to save libmutton.ini: "+err.Error(), back.ErrorWrite, true)

core/utilitiesUNIX.go

@@ -0,0 +1,12 @@
+//go:build !windows
+
+package core
+
+import "syscall"
+
+// setUmask sets the file mode creation mask (umask) for the current process.
+// The call to syscall.Umask needs to be embedded in another function to allow
+// compilation on Windows.
+func setUmask(umask int) {
+	syscall.Umask(umask)
+}

core/utilitiesWIN.go

@@ -0,0 +1,8 @@
+//go:build windows
+
+package core
+
+// setUmask is a dummy function on Windows.
+func setUmask(umask int) {
+	return
+}