Linux Chapter 9

fg

After a background process has been started, what command below can be used to move it to the foreground?

True

After a process has been started, you can change its priority by using the renice command.

True

Each process can start an unlimited number of other processes.

64

How many different kill signals can be sent by the kill command to a given process?

/var/spool/at

On a Fedora based system, where are the shell environment and scheduled commands for at stored?

False

The killall command uses the PID to kill a process.

parent process ID

What can be used on a Linux system to trace the lineage of each child process?

&

What character, when appended to a command, causes the command to be run in the background?

pstree

What command below is used to display the lineage of a process by tracing its PPIDs until the init daemon?

2; SIGINT

What kill signal and number can be used to send an interrupt signal to a process, and is the same as using the Ctrl_c combination to kill a running process?

SIGHUP

What kill signal stops a process, then restarts it with the same PID?

127

What number indicates the lowest kernel priority (PRI) process possible?

-e

What option can be used with the ps command to display an entire list of processes across all terminals and including daemons?

-e

What option, when added to the crontab command, opens the vi editor with a user's cron table?

9; SIGKILL

What signal name and number function as the absolute kill signal, and when issued, forces the Linux kernel to stop executing the process by sending the process's resources to /dev/null?

kill; killall

What two commands below can be used to stop a process, either by PID number or process name?

init; systemd

What two processes below will show up as PID 1, depending on whether a system uses UNIX SysV or System init processes?

-l; -f

What two ps options can be used to display a full list of information about each process, and a long list of information about each process?

%

When killing a background job with the kill command, the background job ID must be prefixed by what character below?

+

When there are multiple background processes executing in the shell, the jobs command indicates the most recent one with which symbol?

The process is high priority.

When viewing the output of the ps ax command, what does a < symbol in the STAT column indicate for a process?

SIGQUIT

Which kill signal terminates a process by taking the process information in memory and saving it to a file called core on the hard disk in the current working directory?

device calls

Which of the following is not one of the three main types of Linux commands?

True

Zombie processes are also known as defunct processes.

True

If the /etc/at.allow and /etc/at.deny files do not exist the root user is allowed to schedule tasks using the at daemon.

sixth

In a cron table entry, what field specifies the absolute pathname to a command that is to be executed?

-l

In order to display a list of at job IDs, what option can be specified to the at commands?

process state

In the output of th ps -l command, what column is the most valuable to systems administrators because it indicates what the process is currently doing?

The process is currently running on the processor.

In the process state column, what does an "R" indicate?