Re: [21.4] Hangs when talking with editres

Nickolay Pakoulin wrote: [snip] I get the same result here (BadWindow error for X_GetWindowAttributes, XEmacs hangs). However, I note that it only applies to the toolbar. Selecting scrollbars or the EmacsFrame widget works correctly. Selecting the menu bar identifies the Shell rather than the menu bar itself, but doesn't hang. Also, I have a more informative backtrace (my X libs have debug info): #0 0x405200de in __select () from /lib/libc.so.6 #1 0x40383d2c in __DTOR_END__ () from /usr/X11R6/lib/libX11.so.6 #2 0x402f6c67 in _XRead (dpy=0x864f0b0, data=0xbfffbb9c "\n\003r\006.", size=32) at XlibInt.c:1037 #3 0x402f76a3 in _XReply (dpy=0x864f0b0, rep=0xbfffbb9c, extra=0, discard=1) at XlibInt.c:1672 #4 0x402e2f32 in XGetWindowAttributes (dpy=0x864f0b0, w=0, attr=0xbfffbbe8) at GetWAttrs.c:113 #5 0x40263073 in PositionInChild (child=0x87469a0, x=368, y=41) at EditresCom.c:1351 #6 0x40263127 in _FindChild (parent=0x86fd658, x=368, y=41) at EditresCom.c:1384 #7 0x402631cb in DoFindChild (w=0x86fc158, event=0x86edde8, stream=0x4026c894) at EditresCom.c:1429 #8 0x4026210b in ExecuteCommand (w=0x86fc158, sel=405, ident=2 '\002', event=0x86edde8) at EditresCom.c:534 #9 0x4026200a in GetCommand (w=0x86fc158, data=0x2, selection=0xbfffdda0, type=0xbfffdd70, value=0x86eddc8, length=0xbfffdd78, format=0xbfffdd74) at EditresCom.c:461 #10 0x40296afa in HandleNormal (dpy=0x864f0b0, widget=0x86fc158, property=274, info=0x87080a0, closure=0x2, selection=405) at Selection.c:1310 #11 0x40296df1 in HandleSelectionReplies (widget=0x86fc158, closure=0x87080a0, ev=0xbfffdfc8, cont=0xbfffde0f "\001") at Selection.c:1408 #12 0x4028515b in CallEventHandlers (widget=0x86fc158, event=0xbfffdfc8, mask=2147483648) at Event.c:841 #13 0x402853a2 in XtDispatchEventToWidget (widget=0x86fc158, event=0xbfffdfc8) at Event.c:952 #14 0x40285c15 in _XtDefaultDispatcher (event=0xbfffdfc8) at Event.c:1417 #15 0x40285f5d in XtDispatchEvent (event=0xbfffdfc8) at Event.c:1497 #16 0x40290787 in XtAppProcessEvent (app=0x838d778, mask=1) at NextEvent.c:1407 #17 0x081e43b5 in emacs_Xt_next_event (emacs_event=0x86d4074) at event-Xt.c:2725 Note that frame #4 has w=0, which explains the BadWindow error. The code corresponding to frame #5 is: if (XtIsWidget(child) && !(mapped_when_managed && XtIsManaged(child))) { XWindowAttributes attrs; if (XGetWindowAttributes(XtDisplay(child), XtWindow(child), &attrs) && attrs.map_state != IsViewable) return (False); } So, we appear to have a valid widget with no window. Which widget? $2 = {core = {self = 0x87469a0, widget_class = 0x8253d80, parent = 0x86fd658, xrm_name = 1486, being_destroyed = 0 '\000', destroy_callbacks = 0x8712b10, constraints = 0x0, x = 0, y = 0, width = 25, height = 12, border_width = 0, managed = 0 '\000', sensitive = 1 '\001', ancestor_sensitive = 1 '\001', event_table = 0x0, tm = {translations = 0x8746778, proc_table = 0x0, current_state = 0x0, lastEventTime = 0}, accelerators = 0x0, border_pixel = 0, border_pixmap = 2, popup_list = 0x0, num_popups = 0, name = 0x8702cae "scrollbar_65539", screen = 0x86aadf0, colormap = 32, window = 0, depth = 16, background_pixel = 52857, background_pixmap = 2, visible = 1 '\001', mapped_when_managed = 1 '\001'}} I.e. "scrollbar_65539". There are two scrollbars; 65538 is the vertical one (width = 15, height = 895), so 65539 must be the horizontal one. But the horizontal one isn't displayed unless truncate-lines is t. Presumably it's being created at startup but not realised until necessary. Personally, I consider this to be a bug in libXmu; it ought to be calling XtIsRealized() on the widget before trying to use its window. Also, I'm not sure how much XEmacs can do about it, given that the last XEmacs function in the backtrace is XtDispatchEvent(). OTOH, win light of both this and the SelectionRequest/BadWindow hangs, I'm starting to suspect a flaw in the X error handler (OTOH, it doesn't help that the "officially" correct behaviour for error handlers involves terminating the application). -- Glynn Clements <glynn.clements(a)virgin.net&gt;