Some missing features of ksh and sh?

netbsdnoob

Hello everyone, I am trying to learn a bit of ksh and sh and these are things I am missing from bash.

I used alt+. (alt and dot) to get the latest argument used in the previous command, is there any way to do this with ksh?
how do i source a file with .sh? I had a file with some variables set and i tried "source script.sh", ". script.sh", "sh script.sh" but none of them worked.

Any good cheatsheet of keyboard shortcuts for sh and ksh?

P.S.: MOst of bash and ksh shortcuts don't work in sh but i kind of expected it

nettester

netbsdnoob how do i source a file with .sh? I had a file with some variables set and i tried "source script.sh", ". script.sh", "sh script.sh" but none of them worked.

Can you give a bit more details why it doesn't work? I don't see why sourcing a file wouldn't work in ksh/sh.

JuvenalUrbino

netbsdnoob is there any way to do this with ksh?

You can use the special $_ argument:

# ls /usr/pkgsrc                                                                                  
[...]
# cd $_ 
# pwd
/usr/pkgsrc

netbsdnoob how do i source a file with .sh? I had a file with some variables set and i tried "source script.sh", ". script.sh", "sh script.sh" but none of them worked.

Using the built-in . (dot) command.

Any good cheatsheet of keyboard shortcuts for sh?

Yes, the man page; if you search for source inside sh(1), you immediately get to:

     . file
            The dot command reads and executes the commands from the specified
            file in the current shell environment.  The file does not need to
            be executable and is looked up from the directories listed in the
            PATH variable if its name does not contain a directory separator
            (‘/’).  The return command (see below) can be used for a premature
            return from the sourced file.

nettester Can you give a bit more details why it doesn't work? I don't see why sourcing a file wouldn't work in ksh/sh.

source is not POSIX; . (dot) instead is standardized (at least since 1003.1, 2004).

rvp

netbsdnoob I used alt+. (alt and dot) to get the latest argument used in the previous command, is there any way to do this with ksh?

Not sure about ksh, but, sh is built with editline(7), so you can create macros. Put this in your ~/.editrc:

bind -s ^[. ^P^[b^K^N^Y

That should do the same thing as bash.
(Note that the above are not control chars. They're plain ASCII chars: ^, [, etc.)

netbsdnoob how do i source a file with .sh?

The . (dot) command searches the PATH, so unless . is present in PATH, you have to do:

. ./somefile.sh

netbsdnoob

nettester it's just in sh actually , with ksh it works.

I don't know it "recommends" me to not try to source files with the root account but i need to.

nettester

netbsdnoob I don't know it "recommends" me to not try to source files with the root account

Oh that's kinda wild. Never seen that before. Just for clarification: Does it actually refuse to source the file or does it just nag you to not do so? If it's the latter you could obviously just ignore it but i understand that the message would be still anoying. I sadly have no idea how to stop it from second guessing your instructions but from pure feeling i'd check if there is some option you can adjust with set.

nettester

JuvenalUrbino source is not POSIX; . (dot) instead is standardized (at least since 1003.1, 2004).

Yes, it was kinda obvious one form had to be non-standard but sadly i am quite awful at POSIX when it comes to shell scripting (besides knowing that i really should use backticks instead of $( ... ) and avoiding pure bashisms as those are a total plague these days). From his description it seems he already tried . though. It just gave him some kind of warning (or error?) to not source files as root. At least that's how i understand it.

netbsdnoob

rvp

wow how do i learn about these bind commands? how do i even read it?

rvp

netbsdnoob All this is documented in the editrc(5) and editline(7) man-pages. After you read thos, you do some experiments. In this case, what we want to do is:

Go back a line: ed-prev-history = Ctrl-P.
(The cursor is left at the end of the line.)
Move to beginning of word: ed-prev-word = Alt-B
(Alt is translated to ESC ie. ^[ by xterm.
Note: the NetBSD console does not do this by default)
Cut the line from here ("point" in editor terminology) to the end of the line: ed-kill-line = Ctrl-K.
(I looked for a copy-to-end-of-line command, but, that doesn't exist. I then tried with em-set-mark and em-copy-region, but, inserting the former (^@) provokes a bug in libeditline. Then, I tried ed-kill-line, which thankfully--and unlike in bash--doesn't delete the text in the history...)
Go to next history line: ed-next-history = Ctrl-N
Paste the "cut" text at point: em-yank = Ctrl-Y