What is Tpgid?

tpgid TPGID ID of the foreground process group on the tty (terminal) that the process is connected to, or -1 if the process is not connected to a tty.

What is PSR ps?

Selects the running processes by doing two UNIX ps commands, separated by a specified sampling period n (default 1s), and comparing the CPU usage of the processes. Whenever possible, this command tries to identify the D3 process from the status returned by the UNIX ps command.

What is TTY in ps output?

A TTY is a computer terminal. In the context of ps , it is the terminal that executed a particular command. The abbreviation stands for “TeleTYpewriter”, which were devices that allowed users to connect to early computers.

What does ps aux do?

The POSIX and UNIX standards require that “ps -aux” print all processes owned by a user named “x”, as well as printing all processes that would be selected by the -a option. If the user named “x” does not exist, this ps may interpret the command as “ps aux” instead and print a warning.

Which command will tell you how long a system has been running?

Uptime
Uptime is a command that returns information about how long your system has been running together with the current time, number of users with running sessions, and the system load averages for the past 1, 5, and 15 minutes.

What does Pkill do in Linux?

pkill is a command-line utility that sends signals to the processes of a running program based on given criteria. The processes can be specified by their full or partial names, a user running the process, or other attributes.

How long the system is running in Linux?

Uptime Command In Linux: It is used to find out how long the system is active (running). This command returns set of values that involve, the current time, and the amount of time system is in running state, number of users currently logged into, and the load time for the past 1, 5 and 15 minutes respectively.

How to set the pgid of a process?

The preferred, POSIX.1-specified ways of doing this are: getpgrp (void), for retrieving the calling process’s PGID; and setpgid (), for setting a process’s PGID. setpgid () sets the PGID of the process specified by pid to pgid . If pid is zero, then the process ID of the calling process is used.

When to use getpgrp or setpgid ( 0, 0 )?

If pid is zero, the process ID of the calling process is used. (Retrieving the PGID of a process other than the caller is rarely necessary, and the POSIX.1 getpgrp () is preferred for that task.) The System V-style setpgrp (), which takes no arguments, is equivalent to setpgid (0, 0) .

What does errno mean in setpgid ( 2 )?

On error, -1 is returned, and errno is set to indicate the error. The POSIX.1 getpgrp () always returns the PGID of the caller. getpgid (), and the BSD-specific getpgrp () return a process group on success. On error, -1 is returned, and errno is set to indicate the error.