Track error status of the command in the line properties.

src/Screen.cpp

@@ -2346,6 +2346,26 @@ void Screen::setReplMode(int mode)
     }
 }
 
+void Screen::setExitCode(int /*exitCode*/)
+{
+    int y = _cuY - 1;
+    while (y >= 0) {
+        _lineProperties[y].flags.f.error = 1;
+        if (_lineProperties[y].flags.f.prompt_start) {
+            return;
+        }
+        y--;
+    }
+    while (y > -_history->getLines()) {
+        LineProperty prop = _history->getLineProperty(y + _history->getLines());
+        prop.flags.f.error = 1;
+        _history->setLineProperty(y + _history->getLines(), prop);
+        if (prop.flags.f.prompt_start) {
+            return;
+        }
+        y--;
+    }
+}
 void Screen::fillWithDefaultChar(Character *dest, int count)
 {
     std::fill_n(dest, count, Screen::DefaultChar);

src/Screen.h

@@ -579,6 +579,7 @@ public:
      * REPL_OUTPUT
      */
     void setReplMode(int mode);
+    void setExitCode(int exitCode);
     /** Return true if semantic shell integration is in use. */
     bool hasRepl() const
     {

src/Vt102Emulation.cpp

@@ -1067,7 +1067,14 @@ void Vt102Emulation::processSessionAttributeRequest(const int tokenSize, const u
         auto list = value.split(QLatin1Char(';'));
         for (int i = 1; i < list.size(); i++) {
             int eq = list.at(i).indexOf(QLatin1Char('='));
-            if (eq > 0) {
+            if (i == 1 && value[0] == QLatin1Char('D')) {
+                // Special case - exit code without '='
+                params[QLatin1String("exit_code")] = list.at(1);
+                int exitCode = list.at(1).toInt();
+                if (exitCode) {
+                    _currentScreen->setExitCode(exitCode);
+                }
+            } else if (eq > 0) {
                 params[list.at(i).mid(0, eq)] = list.at(i).mid(eq + 1);
             }
         }

src/characters/Character.h

@@ -41,6 +41,7 @@ public:
             uint output_start : 1;
             uint input_start : 1;
             uint output : 1;
+            uint error : 1;
         } f;
     } flags;
     qint16 length;