topic Re: Echo and execute a command in Operating System - HP-UX

Echo and execute a command

Ed Hon — Fri, 02 Mar 2001 22:00:38 GMT

Inside a Unix script, is there a way of echoing and executing a Unix command in a single line?

Re: Echo and execute a command

Madhu Sudhan_1 — Fri, 02 Mar 2001 22:04:46 GMT

Ed :

#!/usr/bin/sh
echo date | sh

...Madhu

Re: Echo and execute a command

Bill Hassell — Sat, 03 Mar 2001 02:51:52 GMT

Perhaps what is needed is a way to show a command then show the results. How about something like:

CMD="vgdisplay -v | grep -i name | grep -iv lv"
echo "$CMD \n\n$(eval $CMD)"

Change the last value from lv to pv:

CMD="vgdisplay -v | grep -i name | grep -iv pv"
echo "$CMD \n\n$(eval $CMD)"

I use this technique to document inventory scripts that report on system components. That way, when someone notices an interesting listing, they don't have to ask "How'd you do that?"

The string of command(s) can contain variables so you can even customize the command, document it and then run it.

BTW: The above 2 command strings do a great job in laying out LVM structures in an easy to read format.

Re: Echo and execute a command

Tom Rosenfeld — Tue, 13 Mar 2001 09:31:08 GMT

What about plain old 'set -v' this will echo all commands before execution.

Re: Echo and execute a command

Philip Chan_1 — Tue, 13 Mar 2001 10:08:44 GMT

Just another option for you to consider, do nothing to your script but run shell with the -x switch,

eg 1.
ksh -x
eg 2.
sh -x
This way the command being executed will be printed out first then follow by the actual execution.