[Crash-utility] Re: paging command [was Re: crash CPU bound waiting for user response]

[D. Hugh Redelmeier]

[I hope that you don't mind my jumping in with both feet.  I think
that fresh eyes are valuable.  After a short time one gets used to
things and no longer notices what would newbies stumble over.]

| From: Dave Anderson <anderson at redhat.com>

| D. Hugh Redelmeier wrote:
| > | > ==> It does not say in what way the terminal is not fully functional.

| > It seems to be coming from /usr/bin/less.

| Based upon running within that emacs/Jove environment I guess?

Based on $TERM ("vanilla") and the corresponding termcap or terminfo
entry.  To see this, try:
	TERM=vanilla less /etc/fstab

| > The code in main.c:setup_environment ought to use the PAGER
| > environment variable if it is defined.

| I prefer not to change the default behaviour based upon the
| user's PAGER variable.

The PAGER variable is a UNIX/Linux convention.  Not too well
documented, but real.  Kind of like EDITOR and VISUAL.

Now that I know how to avoid the problem, I don't care much for my own
sake.

| Yeah, the man page is pretty simple-minded.  As you can see, I didn't
| write it, preferring to keep crash usage documentation self-contained
| within the utility itself.

Man pages are another good and longstanding UNIX/Linux tradition.

At a minimum, the man page should say that it is incomplete and that
the definitive documentation is the help command.  It should also have
a FILES section to point out  ~/.crashrc.



BTW, I tried
	set edit emacs
and got
	set: cannot change editing mode during runtime

I don't think that it would be hard to fix this:

- in cmdline.c:readline_init, change all calls to rl_bind_key to be
  calls to rl_bind_key_in_map using the vi_movement_keymap keymap.
  This way the emacs map won't get damaged.

  Move these binding commands out of the "if" -- they need to be
  executed unconditionally.

- each time where you would print the error message "cannot change
  editing mode...", just do change it (i.e. change rl_editing_mode and
  pc->editing_mode).

  Is there a reason to have a pc->editing_mode?  Could rl_editing_mode
  suffice?

Note: I have not tested this and I've never programmed any readline
calls, so I might well be missing something.