Chapter 4 - killall & pkill

Sudoaptgetgood

Hi there! I am an old dog learning new tricks, but isn't below formula wrong?

Chapter 4 - killall & pkill

pkill sends a signal to a process using selection criteria:

$ pkill [-signal] [options] [pattern]

I think signal and options should be reversed. What do you guys think?

coop

"-signal" is an option so the order is irrelevant. It is just showing special attention to the -signal option. Just try it (before posting). The following lines all do the same thing:
pkill -44 -u 1000 cat
pklll cat -u 1000 -44
pkill -u 1000 cat -44

etc, order is irrelvant, even where the pattern goes

Sudoaptgetgood

Thanks for explaining! Since I'm a fish, I tend to take instructions very literally, plus order helps me remember this stuff.
I think the explanation in the course threw me off, where I saw -u as an option, libby as process name, and foobar as identificator within the process. That being said, I think [-signal] was the one that confused me the most. Nevertheless, you are right. I will test in the future before asking any questions here.

course expl:

$ pkill [-signal] [options] [pattern]

For example:

$ pkill -u libby foobar

will kill all of libby's processes with a name of foobar.

luisviveropena

Hi,

You always can do 'man ' to see the available information of the associated man pages about the command. In this case 'man pkill' shows the following:

PGREP(1) User Commands PGREP(1)

NAME
pgrep, pkill - look up or signal processes based on name and other attributes

SYNOPSIS
pgrep [options] pattern
pkill [options] pattern

DESCRIPTION
pgrep looks through the currently running processes and lists the process IDs which match the selection criteria to stdout. All the criteria have to match. For example,

[...]

OPTIONS
-signal
--signal signal
Defines the signal to send to each matched process. Either the numeric or the symbolic signal name can be used. (pkill only.)

[...]

Regards,
Luis.