[SOLVED] Add long command to an alias.

linustalman · 10-27-2015, 09:22 AM

Hi all at LQ.

How do I add this long command to an alias?

Code:

alias ck=sudo apt-get purge $(dpkg -l linux-{image,headers}-"[0-9]*" | awk '/ii/{print $2}' | grep -ve "$(uname -r | sed -r 's/-[a-z]+//')")

If I add as above I get the errors:

Code:

bash: alias: apt-get: not found
bash: alias: purge: not found

If I add single quotes at the start and end, it only partially works.

ck = clean kernels. ^_^

thesnow · 10-27-2015, 10:20 AM

try this:

Code:

ck() {
  sudo apt-get purge $(dpkg -l linux-{image,headers}-"[0-9]*" | awk '/ii/{print $2}' | grep -ve "$(uname -r | sed -r 's/-[a-z]+//')")
}

pan64 · 10-27-2015, 10:21 AM

write a shell script or a function and use that instead of this alias.

ondoho · 10-28-2015, 01:49 AM

LinusStallman, just to elaborate, aliases are not designed to handle this kind of script.
and a script it is, though it is a one-liner.

you can really just add the function into your .bashrc or where-ever you have your aliases.
though i'd suggest to change it to a multiliner instead of a oneliner with pipes.

chrism01 · 10-28-2015, 05:37 AM

This is also a good time to point out that alias definitions are parsed when they are created (ie at login or equiv), not when called.

As above, use a fn instead.

zhjim · 10-28-2015, 08:18 AM

Quote:

Originally Posted by ondoho

though i'd suggest to change it to a multiliner instead of a oneliner with pipes.

Why is that?
And how would you do it?
Besides from redirecting output to a file and then reread it with the next command? Or do you mean just multiple sed commands?

pan64 · 10-28-2015, 08:48 AM

something like that:

Code:

ck() {
  VAR=$(uname -r | sed -r 's/-[a-z]+//')
  VAR2=$(dpkg -l linux-{image,headers}-"[0-9]*" | awk '/ii/{print $2}' | grep -ve "$VAR")
  sudo apt-get purge $VAR2
}

(not tested)

zhjim · 10-28-2015, 10:37 AM

That makes sense. Thanks pan64

linustalman · 10-31-2015, 05:39 AM

Quote:

Originally Posted by thesnow

try this:

Code:

ck() {
  sudo apt-get purge $(dpkg -l linux-{image,headers}-"[0-9]*" | awk '/ii/{print $2}' | grep -ve "$(uname -r | sed -r 's/-[a-z]+//')")
}

Hi thesnow.

This worked fine. Thank you.

linustalman · 10-31-2015, 02:26 PM

Hi chrism01, ondoho, pan64, thesnow, & zhjim.

Thank you all for the info.