Add int Fl::system(const char *command) static member function.

FL/Fl.H

@@ -1334,6 +1334,7 @@ int main() {
    */
   static int draw_GL_text_with_textures() { return draw_GL_text_with_textures_; }
 
+  static int system(const char *command);
 
 #ifdef FLTK_HAVE_CAIRO
   /** \defgroup group_cairo Cairo Support Functions and Classes

src/Fl.cxx

@@ -2098,6 +2098,11 @@ void Fl::keyboard_screen_scaling(int value) {
   Fl_Screen_Driver::keyboard_screen_scaling = value;
 }
 
+/** Run a command line on the computer */
+int Fl::system(const char *command) {
+  return Fl::system_driver()->system(command);
+}
+
 // Pointers you can use to change FLTK to another language.
 // Note: Similar pointers are defined in FL/fl_ask.H and src/fl_ask.cxx
 FL_EXPORT const char* fl_local_shift = Fl::system_driver()->shift_name();