One Day One Cmd

Place for playing with commands…

Day 85: $kill command

ODOC: About kill command

The kill command can Cancels a job.

Syntax

kill [-s] [-l] %pid

-s -> Specify the signal to send, using one of the symbolic names defined in the description. Values of signal will be recognized in a case independent fashion, without the SIG prefix. In addition, the symbolic name 0 will be recognized, representing the signal value zero. The corresponding signal will be sent instead of SIGTERM.

-l -> Write all values of signal sup ported by the implementation, if no operand is given. If an exit_status operand is given and it is a value of the ? shell special parameter and wait corresponding to a process that was ter minated by a signal, the signal corresponding to the signal that terminated the process will be written. If an exit_status operand is given and it is the unsigned decimal integer value of a signal number, the signal corresponding to that signal will be written. Otherwise, the results are unspecified.

pid -> One of the following:

1. A decimal integer specifying a process or process group to be signaled. The process or processes selected by positive, negative and zero values of the pid operand will be as
described for the kill function. If process number 0 is specified, all processes in the process group are signaled. If the first pid operand is negative, it should be preceded by — to keep it from being interpreted as an option.

2. A job control job ID that identifies a background process group to be signaled. The job control job ID notation is applicable only for invocations of kill in the current shell execution environment.

Note the job control job ID pid is available only on systems supporting the job control option.

Examples

praveen@praveen-desktop:~$ kill -s kill 100 -165

Kills job 1 of uid 165

When running the kill command you may receive the error “Operation not permitted”, this is often encountered when you’re killing the wrong group id (often 1,2,3 or low number jobs) that you don’t have permission to kill. If you wish to see the group id of the background task run jobs -l

With Regards,
S. Praveen

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: