On Sun 22 Jan 2023 at 03:50:17 (+0100), Vincent Lefevre wrote: > The following issue is reproducible in several terminals, e.g. xterm > and GNOME Terminal, and several shells, e.g. bash and zsh. > > 1. From the shell in an X terminal emulator, run an X application > in foreground, e.g. emacs-gtk or xterm. > > 2. Paste a long text (e.g. the contents of /usr/share/doc/libc6/copyright > to choose an example every one has) in the terminal. Actually, only > the beginning of the text appears in the terminal.
Well, strictly, I see the end of the first portion of the pasted file. The input buffer of xterm fills up, ironically at "Por" in one of the lines containing "Portions Copyright … …". The beginning of the file /usr/share/doc/libc6/copyright has scrolled off the top by then. > 3. Type Ctrl-C (one or several times) in the terminal. > But nothing happens. I presume that's because the input buffer is already full, so you'd need what I think they called an out-of-band signal, like pressing Break used to do on an old teletype terminal. > 4. Quit the X application that was started at step 1. > > Result: many lines of the pasted text are executed by the shell! > > This issue doesn't occur when the pasted text is short: the Ctrl-C > kills the X application via a SIGINT and nothing is executed. Yes, because in this case, ^C makes it into the input to xterm. > You may wonder why one would paste a long text at step 2. In fact, > this happens by accident: I sometimes paste data in the terminal > instead of the application (typically Emacs). And this is really > annoying, in particular when lines contains the ">" character, > which has the effect to create files. > > Is there any way to avoid this issue? Make sure that the application's data is saved, eg, ^X^S in emacs, but don't exit the application, eg, ^X^C in emacs. Then click on the X that closes the xterm window, which takes down both xterm and the application with it. This is effectively an out-of-band signal. Finally, open another xterm with your WM's menu, to replace it. Cheers, David.
