Date: Thu, 14 Mar 1996 09:41:02 +1100 From: Bruce Evans <bde@zeta.org.au> To: lehey.pad@sni.de, terry@lambert.org Cc: hackers@FreeBSD.ORG Subject: Re: using ddb to debug a double-panic? Message-ID: <199603132241.JAA03816@godzilla.zeta.org.au>
next in thread | raw e-mail | index | archive | help
>> 4DOS/DOSKey/WinICE/FANSIConsole/DCL/TPU/EDT/tcsh/ksh(the real one)/etc. >> all use: >> >> 1) Cursor up: previous command (repeat to the limits of the >> command recall buffer). >OK. Alternative: ^P All cursor keys can't work on serial consoles (no termcap in the kernel). >> 3) Partial command, then cursor up/down: command previous/next >> beginning with partial command as line prefix. >I don't see the need for this. It's different from other It's a weak form of i-seach. Alternative: ^R/^S (or whatever is used to get around ^S being the stop char). >> 4) Abort key (^C): discard edits, new input line. >OK, I suppose. Alternative to ^U? In bash, ^C differs from ^U in that it prints a newline and discards the whole line. ^U only discards the part of the line to the left of the cursor. >> 6) Delete: delete character to right of cursor >OK, I suppose. Alternative: ^D. Not OK? ASCII Del does the same as ^H in bash, although this is only useful if the backspace key is misbound to Del. >> 7) Insert: toggle insertion/overstrike; default overstrike (on >> VMS programs, can change default as a preference... on 2 of >> the DOS programs, the previous in-ude mode is remembered -- >> the toggle is global, not per entry line). >I hadn't planned on insert mode at all. Does anybody else have any >ideas on this? Insert mode should be the default (as in bash). >> The one problem is the "backspace deletes left" for terminals where >> the cursor left key emits "^H". In these situations, the BS key >> becomes synonymous with the cursor left key and the "delete character >> to left of cursor" function is lost. >I think that, under these circumstances, I'd opt for the cursor left >function being "lost" (i.e. only available via ^B). Recall that we're >talking console only here, of course, so the difference is moot. Yes, there are plenty of differences for the console to discuss :-): - only broken terminals don't emit ^H for backspace :-) - ^H should mean delete character to the left of the cursor. This goes well with (ASCII) Del(ete) meaning to delete the character to the right of the cursor. Use left arrow or ^B to backspace without delete. - the pcvt console is broken and emits ASCII Del for backspace :-) - the syscons console correctly emits ASCII backspace for backspace. - the kernel debugger shouldn't depend on the kernel device drivers so the different behaviour of the console drivers should be irrelevant. BTW I noticed some bugs in pcvt after booting with -c to look at how the command line editor in the non-visual userconfig handles Backspace vs Delete: - I boot with a BIOS option to keep NumLock off. The NumLOck LED is off in userconfig but is apparently on in pcvt (Del gives `.'). - after hitting NumLock to get pcvt in sync with the LED (off), Del acts strangely. It has no effect until the next character, then the next character and/or the edit buffer are messed up. This may be the same problem that prevents the visual config from working at all. Bruce
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199603132241.JAA03816>