Re: spurious CR/LF on tty (was: how to remove GUI)
On Mon 21 Sep 2020 at 12:16:53 (+1000), David wrote: > On Mon, 14 Sep 2020 at 21:56, Greg Wooledge wrote: > > > There are many ways to work around it. My preferred way is to clear > > the screen with Ctrl-L (ESC Ctrl-L for me, because I use bash in vi > > mode). That will redraw the shell prompt and the partially typed > > command after clearing the screen, and allow you to continue typing. > > Thank you very much for that advice. I was not aware that bash > "clear-screen" has the feature of repainting the partially typed > command. This exactly addresses what was causing my concern, so I am > less troubled by this now. BTW, I failed to point out earlier that Ctrl-L is a safer workaround than Ctrl-U Enter Ctrl-Y for one other reason: Ctrl-L is not adjacent to the Enter key. You might say "but neither is Ctrl-U", but actually it is—it's adjacent to Ctrl-J (≡ Enter). Cheers, David.
Re: spurious CR/LF on tty (was: how to remove GUI)
On Mon, 14 Sep 2020 at 21:56, Greg Wooledge wrote: > On Sun, Sep 13, 2020 at 09:14:54PM -0500, David Wright wrote: > > On Sat 12 Sep 2020 at 21:45:34 (+1000), David wrote: > > > And regarding "just hit the enter key ... and all is fine", this > > > behaviour does not just occur at a login prompt. If you login quickly > > > as root to a minimal install as I often do, this behaviour occurs > > > during root console use, and if one is half-way through typing a > > > command which suddenly disappears from view, pressing enter could be a > > > recipe for disaster. > > > (eg dd before I have added the count= parameter). > > > So my habit when it occurs has become to: ctrl-u, enter, ctrl-y. > It's the same general kind of problem that you can face during terminal > usage in many situations. Something unexpectedly scribbles on your > terminal while you're typing, whether it's modem line noise, or the > kernel warning all users of an imminent reboot, or a background job > you forgot you had running, or whatever. > There are many ways to work around it. My preferred way is to clear > the screen with Ctrl-L (ESC Ctrl-L for me, because I use bash in vi > mode). That will redraw the shell prompt and the partially typed > command after clearing the screen, and allow you to continue typing. Thank you very much for that advice. I was not aware that bash "clear-screen" has the feature of repainting the partially typed command. This exactly addresses what was causing my concern, so I am less troubled by this now. For curiosity, I had a look at 'man bash' (on buster), it hints about this feature in a way that might seem clear to someone who already knew it, but does not communicate it clearly to me (ie someone with no prior knowledge of it). "clear-screen: Clear the screen leaving the current line at the top of the screen." The word "leaving" is what misdirects me. Without knowing the actual behaviour, that sentence suggests to me that the *current* (ie broken or invisible) line would be *left* (ie unchanged) at the top. The sentence would better describe to me the useful behaviour if it read something like: "clear-screen: Clear the screen, redrawing the current line at the top of the screen." or "clear-screen: Clear the screen, placing the current line at the top of the screen, and redrawing any readline buffer contents."
Re: spurious CR/LF on tty (was: how to remove GUI)
On Sun, Sep 13, 2020 at 09:14:54PM -0500, David Wright wrote: > On Sat 12 Sep 2020 at 21:45:34 (+1000), David wrote: > > And regarding "just hit the enter key ... and all is fine", this > > behaviour does not just occur at a login prompt. If you login quickly > > as root to a minimal install as I often do, this behaviour occurs > > during root console use, and if one is half-way through typing a > > command which suddenly disappears from view, pressing enter could be a > > recipe for disaster. > > > > (eg dd before I have added the count= parameter). > > > > So my habit when it occurs has become to: ctrl-u, enter, ctrl-y. > > I use a different technique when I type commands that I consider > "dangerous" (and dd is always that): > > I type the command starting with # and, when I've finished, > double-check it. Then I press , recall it with ↑, and > press , , , to execute it, which > also avoids the unprotected line ending up in the history stack. It's the same general kind of problem that you can face during terminal usage in many situations. Something unexpectedly scribbles on your terminal while you're typing, whether it's modem line noise, or the kernel warning all users of an imminent reboot, or a background job you forgot you had running, or whatever. There are many ways to work around it. My preferred way is to clear the screen with Ctrl-L (ESC Ctrl-L for me, because I use bash in vi mode). That will redraw the shell prompt and the partially typed command after clearing the screen, and allow you to continue typing.
Re: spurious CR/LF on tty (was: how to remove GUI)
On Sat 12 Sep 2020 at 21:45:34 (+1000), David wrote: > On Sat, 12 Sep 2020 at 05:18, Felix Miata wrote: > > Greg Wooledge composed on 2020-09-11 11:42 (UTC-0400): > > > I only mention it because once in a while, someone sees something like > > > it and freaks out, thinking the computer is locked up or whatever. They > > > don't realize they can just hit the Enter key and get a fresh login > > > prompt, and all is fine. > > > > I have too many installations to keep track of which exhibit this nuisance > > or not, > > but I'm guessing most if not all Buster and Bullseye do it, and maybe even > > Stretch > > & Jessie, which I'm rarely booting any more. > > And regarding "just hit the enter key ... and all is fine", this > behaviour does not just occur at a login prompt. If you login quickly > as root to a minimal install as I often do, this behaviour occurs > during root console use, and if one is half-way through typing a > command which suddenly disappears from view, pressing enter could be a > recipe for disaster. > > (eg dd before I have added the count= parameter). > > So my habit when it occurs has become to: ctrl-u, enter, ctrl-y. I use a different technique when I type commands that I consider "dangerous" (and dd is always that): I type the command starting with # and, when I've finished, double-check it. Then I press , recall it with ↑, and press , , , to execute it, which also avoids the unprotected line ending up in the history stack. > Between that and kernel messages barfing into the terminal text, it's > a pretty shitty user-experience that is embarrassing when observed by > users of any other OS. (FWIW I've always expected a VC to behave like a console.) Cheers, David.
Re: spurious CR/LF on tty (was: how to remove GUI)
On Sat, 12 Sep 2020 at 05:18, Felix Miata wrote: > Greg Wooledge composed on 2020-09-11 11:42 (UTC-0400): > > On Fri, Sep 11, 2020 at 10:35:46 -0500, David Wright wrote: > > >> That's the first mention of this phenomenon I recall seeing since I posted > >> https://lists.debian.org/debian-user/2018/03/msg01030.html > >> (which dealt mainly with a more serious problem). > > >> I never install a DE/DM and all that stuff, but I get the cursor > >> movement nonetheless. Is that what you're saying? > > > It's not as serious as what you reported in the 2018 thread. It's just > > an occasional glitch, not easily reproducible, with a trivial workaround. > > > I only mention it because once in a while, someone sees something like > > it and freaks out, thinking the computer is locked up or whatever. They > > don't realize they can just hit the Enter key and get a fresh login > > prompt, and all is fine. > > I have too many installations to keep track of which exhibit this nuisance or > not, > but I'm guessing most if not all Buster and Bullseye do it, and maybe even > Stretch > & Jessie, which I'm rarely booting any more. And regarding "just hit the enter key ... and all is fine", this behaviour does not just occur at a login prompt. If you login quickly as root to a minimal install as I often do, this behaviour occurs during root console use, and if one is half-way through typing a command which suddenly disappears from view, pressing enter could be a recipe for disaster. (eg dd before I have added the count= parameter). So my habit when it occurs has become to: ctrl-u, enter, ctrl-y. Between that and kernel messages barfing into the terminal text, it's a pretty shitty user-experience that is embarrassing when observed by users of any other OS.
Re: spurious CR/LF on tty (was: how to remove GUI)
On Fri 11 Sep 2020 at 15:18:10 (-0400), Felix Miata wrote: > Greg Wooledge composed on 2020-09-11 11:42 (UTC-0400): > > On Fri, Sep 11, 2020 at 10:35:46 -0500, David Wright wrote: > > >> That's the first mention of this phenomenon I recall seeing since I posted > >> https://lists.debian.org/debian-user/2018/03/msg01030.html > >> (which dealt mainly with a more serious problem). > > >> I never install a DE/DM and all that stuff, but I get the cursor > >> movement nonetheless. Is that what you're saying? > > > It's not as serious as what you reported in the 2018 thread. It's just > > an occasional glitch, not easily reproducible, with a trivial workaround. > > > I only mention it because once in a while, someone sees something like > > it and freaks out, thinking the computer is locked up or whatever. They > > don't realize they can just hit the Enter key and get a fresh login > > prompt, and all is fine. > > I have too many installations to keep track of which exhibit this nuisance or > not, > but I'm guessing most if not all Buster and Bullseye do it, and maybe even > Stretch > & Jessie, which I'm rarely booting any more. For me, it started with stretch and continues with buster (not used bullseye yet). I installed my first stretch on the lenovo with the more serious problem—reporting that was the only reason I also mentioned the spurious CR. (I first thought they might be related, of course.) I hadn't realised anybody else saw them. Apologies to Greg, I misuderstood the import of your posting, thinking that the CR had something to do with configuring a graphical.target without a DM. Duh. I guess you meant that someone new to a VC login, after always having used a DM login in the past, might hit this bug and freak out. Cheers, David.
Re: spurious CR/LF on tty (was: how to remove GUI)
Greg Wooledge composed on 2020-09-11 11:42 (UTC-0400): > On Fri, Sep 11, 2020 at 10:35:46 -0500, David Wright wrote: >> That's the first mention of this phenomenon I recall seeing since I posted >> https://lists.debian.org/debian-user/2018/03/msg01030.html >> (which dealt mainly with a more serious problem). >> I never install a DE/DM and all that stuff, but I get the cursor >> movement nonetheless. Is that what you're saying? > It's not as serious as what you reported in the 2018 thread. It's just > an occasional glitch, not easily reproducible, with a trivial workaround. > I only mention it because once in a while, someone sees something like > it and freaks out, thinking the computer is locked up or whatever. They > don't realize they can just hit the Enter key and get a fresh login > prompt, and all is fine. I have too many installations to keep track of which exhibit this nuisance or not, but I'm guessing most if not all Buster and Bullseye do it, and maybe even Stretch & Jessie, which I'm rarely booting any more. -- Evolution as taught in public schools, like religion, is based on faith, not on science. Team OS/2 ** Reg. Linux User #211409 ** a11y rocks! Felix Miata *** http://fm.no-ip.com/