bugGNU Octave - Bugs: bug #42681, Freeze on Ctrl+s in Console


bug #42681: Freeze on Ctrl+s in Console

Submitted by:  Jonathan Hahn <helo>
Submitted on:  Fri 04 Jul 2014 02:34:40 PM UTC  
Category: GUISeverity: 1 - Wish
Priority: 5 - NormalItem Group: Incorrect Documentation
Status: FixedAssigned to: Mike Miller <mtmiller>
Originator Name: Open/Closed: Closed
Release: devOperating System: GNU/Linux

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Sat 07 Feb 2015 04:23:53 AM UTC, comment #6:

Fixed by disabling output flow control unconditionally in the unix terminal:


Ctrl-S should no longer cause inadvertent freezing, and Ctrl-Q and Ctrl-S can now be configured in readline.

Mike Miller <mtmiller>
Project MemberIn charge of this item.
Sat 07 Feb 2015 12:07:57 AM UTC, comment #5:

I agree, it's pretty risky to leave Ctrl-S bound to flow control in the GUI terminal, and it's basically useless.

I don't remember at the moment, but I think I had a patch already tested to disable flow control in the unix terminal, where there is already some terminal control stuff being done.

Mike Miller <mtmiller>
Project MemberIn charge of this item.
Fri 06 Feb 2015 05:22:07 PM UTC, comment #4:

I would really like to see this fixed as I use the Ctrl+S binding for my own purposes in readline.

I think the problem here is that Ctrl+S is being seen by the terminal emulator and the default behavior of this is not easily overridden. When I use the preferences dialog (Shortcuts, Disable global shortcuts when terminal window has focus) I can disable general shortcut processing like Ctrl+N for New File. But this doesn't work for Ctrl+S. Interestingly, on Windows Ctrl+S brings up the incremental search through history feature. So there must be an actual difference in code between the two terminal implementations in libgui/qterminal/libqterminal/(win32|unix). Maybe the answer lies there.

Rik <rik5>
Project Administrator
Tue 08 Jul 2014 04:48:18 PM UTC, comment #3:

Thanks for confirming. I'm not sure what the right approach should be in this case. Marking as documentation for now, but may also be fixed by disabling this particular readline binding by default when in GUI mode.

Mike Miller <mtmiller>
Project MemberIn charge of this item.
Fri 04 Jul 2014 10:25:06 PM UTC, comment #2:

Yes I mean Ctrl+s. I thought everything was frozen, but you are right. It is only the Console Window.

That the Run-Button at the editor was not working as well confused me.

Maybe there could be a hint for the readline mode in GUI.

Jonathan Hahn <helo>
Fri 04 Jul 2014 03:00:49 PM UTC, comment #1:

Thanks for your bug report. Do you mean that after Ctrl+s you are unable to type in the console window? Or is the entire GUI frozen (unable to click any menus, switch tabs?)

If it's only text entry that is "frozen", this is expected readline behavior with the Ctrl+s key sequence. Enter Ctrl-q to turn on text input again.

Mike Miller <mtmiller>
Project MemberIn charge of this item.
Fri 04 Jul 2014 02:34:40 PM UTC, original submission:

I have Console and Editor upon each other. Sometimes I press Strg+s for saving my script while the cursor still is in Console. After that the GUI is freezed.

Jonathan Hahn <helo>


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  • -unavailable- added by rik5 (Posted a comment)
  • -unavailable- added by mtmiller (Posted a comment)
  • -unavailable- added by helo (Submitted the item)

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    Follow 10 latest changes.

    Date Changed By Updated Field Previous Value => Replaced By
    Sat 07 Feb 2015 04:32:18 AM UTCmtmillerDependencies-=>bugs #43520 is dependent
    Sat 07 Feb 2015 04:23:53 AM UTCmtmillerStatusIn Progress=>Fixed
    Sat 07 Feb 2015 12:07:57 AM UTCmtmillerStatusNeed Info=>In Progress
      Assigned toNone=>mtmiller
    Fri 06 Feb 2015 05:22:07 PM UTCrik5SummaryFreeze on Strg+s in Console=>Freeze on Ctrl+s in Console
    Tue 08 Jul 2014 04:48:18 PM UTCmtmillerSeverity3 - Normal=>1 - Wish
      Item GroupCrash=>Incorrect Documentation
    Fri 04 Jul 2014 03:00:49 PM UTCmtmillerStatusNone=>Need Info

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