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Hello Esteemed Monks,

I have an app using Tk's main window integrated with Term::ReadLine::Gnu in the terminal window. I would like to be able to clean up before exiting on Ctrl-C issued in either window.

With main window focus, I use Tk::bind to associate Ctrl-C with a callback (\&abort) that exits via CORE::exit. Although this causes a hard landing (segfault), the terminal functions normally afterwards.

With terminal window focus, the signal handler exits in the same way, however, after exiting, the terminal fails to echo the characters I type. Leaving via Tk::exit() results in the same echoless state, regardless of how it is invoked.

I suspect the line $OUT = $term->OUT || \*STDOUT (which I cut and pasted) of doing some redirection.

Update:This line provides an output filehandle, however all of my print statements output correctly without writing print $OUT $something.

I also looked at the Term::ReadLine methods such as rl_reset_terminal() without finding a solution.

Update: Issuing $term->rl_deprep_terminal() before exit() appears to solve the problem. (c.f 'man readline')

Here is my (revised) code:

use Tk; my $mw = MainWindow->new; $mw->bind('<Control-Key-c>' => \&abort); use Term::ReadLine; $SIG{INT} = \&abort; my $term = new Term::ReadLine(); loop(); sub loop { $term->tkRunning(1); $OUT = $term->OUT || \*STDOUT; while (1) { my ($user_input) = $term->readline("input>") ; process_line( $user_input ); } } sub abort { # do some cleanup $term->rl_deprep_terminal(); # Update! CORE::exit(); } sub process_line { print "user input: $_[0]\n" }
Update: Including $term->rl_deprep_terminal() in &abort appears sufficient to terminate the application.

In reply to Echoless terminal state after exiting Tk/Term::ReadLine event loop (Solved!) by gnosti

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