On Thu, Mar 21, 2019 at 03:24:48PM +0000, Ian Abbott wrote: > On 21/03/2019 13:33, Michael Olbrich wrote: > > On Thu, Mar 21, 2019 at 12:46:40PM +0000, Ian Abbott wrote: > > > On 20/03/2019 15:41, Michael Olbrich wrote: > > > > On Wed, Mar 20, 2019 at 12:41:47PM +0000, Ian Abbott wrote: > > > > > On 20/03/2019 09:15, Dold, Wolfram wrote: > > > > > > On Tue, 2019-03-19 at 17:42 +0000, Ian Abbott wrote: > > > > > > > On 19/03/2019 12:33, Dold, Wolfram wrote: > > > > > > > > Hi Ian, > > > > > > > > On Tue, 2019-03-19 at 12:06 +0000, Ian Abbott wrote: > > > > > > > > > On 19/03/2019 09:17, Dold, Wolfram wrote: > > > > > > > > > > Hi there, > > > > > > > > > > when we connect via ssh to our embedded device, the > > > > > > > > > > backspace key does not work. > > > > > > > > > > During the analysis we found out that the passage > > > > > > > > > > > > > > > > > > > > # This fixes the backspace when telnetting in. > > > > > > > > > > if [ "$TERM" != "linux" ]; then > > > > > > > > > > stty erase ^H > > > > > > > > > > fi > > > > > > > > > > > > > > > > > > > > from the file '/etc/profile' contained in ptxdist. > > > > > > > > > > > > > > > > > > > > Now I want to ask, how best to fix this behavior? > > > > > > > > > > Can the passage simply be omitted? (At least the comment > > > > > > > > > > lets me assume that, because there 'telnet' is > > > > > > > > > > mentioned > > > > > > > > > > and > > > > > > > > > > that is no longer necessarily state of the art). > > > > > > > > > > Or does omitting it lead to other unwanted side effects? > > > > > > > > > > > > > > > > > > > > Any help would be appreciated. > > > [snip because it's getting a bit long] > > > > > > > > I've no idea why that bit of the /etc/profile file is there, but I > > > > > guess it > > > > > must have suited one of the PTXdist developers at the time. A "git > > > > > blame" > > > > > only revealed that the whole file was added in 2006, so I don't know > > > > > how > > > > > relevant that part of it is today. > > > > > > > > This code was moved around some more. It was actually introduced in the > > > > initial import from CVS in 2003 :-). Telnet works just fine without > > > > this, > > > > so I guess this is no longer needed. > > > > > > Perhaps it was there for the Windows Telnet client which seems to send > > > ASCII > > > BS when the "Backspace" key is pressed and ASCII DEL when the (less > > > conveniently placed) "Delete" key is pressed. This mimics the codes sent > > > by > > > the VT-102 "Backspace" and "Delete" keys which were both conveniently > > > placed. > > > > > > The Windows telnet client has a -t option to set the terminal type to one > > > of > > > "vt100", "vt52", "ansi", or "vtnt", but it doesn't pass the selected > > > terminal type to the server, and this doesn't seem to have any effect on > > > the > > > codes sent by the "Backspace" and "Delete" keys. The TERM environment > > > variable ends up getting set to "vt102" by default on my PTXdist systems > > > if > > > a terminal type hasn't been passed through by the Telnet client. I don't > > > know if that is configurable. > > > > > > The Windows Telnet client isn't installed by default, but can still be > > > installed as a "Windows Feature". I guess most people who used it would > > > have switched to something like PuTTY by now. > > > > I'm pretty sure it was a Linux issue. I remember having problems like this > > a long time ago. > > > > > > I'll be happy to apply a patch that removes this. > > > > > > I'm worried that doing so might annoy some people who expect the existing > > > behavior. > > > > I'd rather fix a real problem. If it causes issues, then we'll try to find > > a solution. > > Changing it would probably annoy gtkterm users, and annoy minicom users less > so. For both of those, the Backspace key sends BS by default. There is an > option to change it to DEL in minicom, but no such option in gtkterm (or if > it exists, it is well hidden!). (Personally, I prefer minimalist, dumb > serial terminal emulators such as picocom, nanocom, and microcom which just > run inside a local terminal session.)
Ok, I did some testing and now I'm rather confused. I tested minicom, microcom and gtkterm on the serial port and putty (on Linux) via serial port and telnet and a normal telnet. In all cases backspace and delete work as expected with 'stty erase ^H' and 'stty erase ^?'. Am I missing something here or is something magically doing the right thing in the background? Michael -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ ptxdist mailing list [email protected]
