Fix CTRL-Z handling

Fix #3802

This fixes `xterm -e fzf` hangs on CTRL-Z

* Replace SIGSTOP with SIGTSTP
* Do not rely on SIGCONT

src/terminal.go

@@ -854,7 +854,6 @@ func NewTerminal(opts *Options, eventBox *util.EventBox, executor *util.Executor
 		mutex:              sync.Mutex{},
 		uiMutex:            sync.Mutex{},
 		suppress:           true,
-		sigstop:            false,
 		slab:               util.MakeSlab(slab16Size, slab32Size),
 		theme:              opts.Theme,
 		startChan:          make(chan fitpad, 1),
@@ -3437,19 +3436,6 @@ func (t *Terminal) Loop() error {
 			}
 		}()
 
-		contChan := make(chan os.Signal, 1)
-		notifyOnCont(contChan)
-		go func() {
-			for {
-				select {
-				case <-ctx.Done():
-					return
-				case <-contChan:
-					t.reqBox.Set(reqReinit, nil)
-				}
-			}
-		}()
-
 		if !t.tui.ShouldEmitResizeEvent() {
 			resizeChan := make(chan os.Signal, 1)
 			notifyOnResize(resizeChan) // Non-portable
@@ -3787,7 +3773,7 @@ func (t *Terminal) Loop() error {
 					case reqRedrawPreviewLabel:
 						t.printLabel(t.pborder, t.previewLabel, t.previewLabelOpts, t.previewLabelLen, t.previewOpts.border, true)
 					case reqReinit:
-						t.tui.Resume(t.fullscreen, t.sigstop)
+						t.tui.Resume(t.fullscreen, true)
 						t.fullRedraw()
 					case reqResize, reqFullRedraw:
 						if req == reqResize {
@@ -4527,11 +4513,11 @@ func (t *Terminal) Loop() error {
 			case actSigStop:
 				p, err := os.FindProcess(os.Getpid())
 				if err == nil {
-					t.sigstop = true
 					t.tui.Clear()
 					t.tui.Pause(t.fullscreen)
 					notifyStop(p)
 					t.mutex.Unlock()
+					t.reqBox.Set(reqReinit, nil)
 					return false
 				}
 			case actMouse:

src/terminal_unix.go

@@ -20,9 +20,5 @@ func notifyStop(p *os.Process) {
 	if err == nil {
 		pid = pgid * -1
 	}
-	unix.Kill(pid, syscall.SIGSTOP)
+	unix.Kill(pid, syscall.SIGTSTP)
-}
-
-func notifyOnCont(resizeChan chan<- os.Signal) {
-	signal.Notify(resizeChan, syscall.SIGCONT)
 }

src/terminal_windows.go

@@ -13,7 +13,3 @@ func notifyOnResize(resizeChan chan<- os.Signal) {
 func notifyStop(p *os.Process) {
 	// NOOP
 }
-
-func notifyOnCont(resizeChan chan<- os.Signal) {
-	// NOOP
-}