topic Re: recall previous command using esc-k in Operating System - HP-UX

recall previous command using esc-k

Joy Conner — Wed, 02 Jun 2010 20:20:30 GMT

I have a unix system that does not recall previous commands. What setting do I need to change to enable this?

Re: recall previous command using esc-k

TwoProc — Wed, 02 Jun 2010 20:35:03 GMT

If it's a Linux box using bash, or another Unix using ksh.

set EDITOR=vi
set -o vi

Try the above without the first line, if it works, great. If not, try it again with the set EDITOR command. If you need both, there's your fix.

If it's bash your using then the default history recall command is ctrl-r. The above changes it to act like ksh.

Re: recall previous command using esc-k

Joy Conner — Wed, 02 Jun 2010 21:07:09 GMT

This did not work.

The system is HPUX B.11.00 and the user is root.

Re: recall previous command using esc-k

TwoProc — Wed, 02 Jun 2010 21:23:38 GMT

type ksh
then try your esc-k commands, if it doesn't work, then try:
set -o vi
then try your esc-k commands, if it doesn't
work, then try
set EDITOR=vi; export EDITOR (export shouldn't be necessary, but doesn't hurt).

Then try your esc-k commands, You should be working now.

FYI: as root, in the default posix shell, you generally don't have history turned on, check HISTSIZE.

echo $HISTSIZE

if this is zero, you don't have history. When you invoke ksh, you'll read the /etc/profile script, which by default has a HISTORY size setting, so this starts to work.

Alternately, you could just try setting HISTSIZE to something other than zero without using ksh. Then try esc-k,
then try setting "-o vi", then try esc-k, then try "set EDITOR=vi",then try esc-k.

When you've finally got a solution working, add the three "set" commands to your ~/.profile in your home directory, which is probably just "/", unless you've changed it.

put this in root's .profile, preferably at the end of the file.

set HISTSIZE=300
set EDITOR=vi
set -o vi

Re: recall previous command using esc-k

Joy Conner — Thu, 03 Jun 2010 11:13:52 GMT

ksh worked. Thank you.

Does this mean that I need to remember to type this command when ever I want to recall?

Re: recall previous command using esc-k

Steven Schweda — Thu, 03 Jun 2010 13:21:24 GMT

> Does this mean that I need to remember to
> type this command when ever I want to
> recall?

If you wish to use command-line recall in a
shell, then you probably need to use a shell
which does command-line recall. If the
normal "root" shell doesn't do it, then you
might need to run some other shell, like,
say, "ksh" or "bash".

Changing the default "root" shell on an
HP-UX system is generally a very bad idea, so
you may be better off manually running the
other shell when you log into the HP-UX
system.

Re: recall previous command using esc-k

Joy Conner — Thu, 03 Jun 2010 13:41:48 GMT

OK. Thank you for your help.

Re: recall previous command using esc-k

TwoProc — Thu, 03 Jun 2010 13:55:05 GMT

Joy, just add the commands into root's home directory in the file called .profile, it's probably at the top of the tree at "/.profile".

Put the three "set" commands there, and when you run "ksh" it will run the contents of the ".profile" file. Oh, yeah and make sure the file is executable for root: "chmod u+x .profile"

Re: recall previous command using esc-k

stephen peng — Thu, 03 Jun 2010 15:32:03 GMT

just enter ksh -o vi after you login

Re: recall previous command using esc-k

TwoProc — Thu, 03 Jun 2010 17:07:25 GMT

My mistake - while what I said will work - the better place to put the "set" commands would be in /.kshrc ; and then make it executable.

Re: recall previous command using esc-k

Bill Hassell — Fri, 04 Jun 2010 01:47:48 GMT

There is a feature (bug?) in the POSIX shell for root. The .sh_history file (which is required for command recall to work) is not automatically created. This has existed for years but may have finally been fixed. ksh will generate the file when HISTFILE and HISTSIZE have been set.

This is fairly annoying so I always put the EDITOR, HISTFILE and HISTSIZE variables in /etc/profile. Now every user gets the correct settings. Using .profile or .kshrc means that the fix must be applied for every user login on the system.

By the way, set HISTFILE to a reasonable value like 10000 (not 300). The purpose is to log previous commands and being able to recall something from 6 months ago can be a very important requirement.

Now you know how to enable the POSIX shell for command history, change root's shell back to /sbin/sh. As mentioned, ksh will not function in single user mode. The POSIX shell and ksh are virtually identical for most sysadmins.

Re: recall previous command using esc-k

TwoProc — Fri, 04 Jun 2010 15:49:19 GMT

Great advice to clarify & summarize final solution Bill - thank you!

Re: recall previous command using esc-k

Joy Conner — Fri, 04 Jun 2010 16:08:28 GMT

Thanks to everyone for helping.