Which pid is assigned to the init program

The process init is the only process that will always have the same PID on any session and on any system, and that PID is 1. This is because init is always the first process on the system and is the ancestor of all other processes. A very large PID does not necessarily mean that there are anywhere near that many processes on a system.

This is because such numbers are often a result of the fact that PIDs are not immediately reused, in order to prevent possible errors. The default maximum value of PIDs is 32, This maximum is important because it is essentially the maximum number of processes that can exist simultaneously on a system. Although this will almost always be sufficient for a small system, large servers may require many more processes. A very large PID does not necessarily mean that there are anywhere near that many processes on a system.

This is because such numbers are often a result of the fact that PIDs are not immediately reused, in order to prevent possible errors.

The default maximum value of PIDs is 32, This maximum is important because it is essentially the maximum number of processes that can exist simultaneously on a system. Although this will almost always be sufficient for a small system, large servers may require many more processes. The lower the maximum value, the sooner the values will wrap around, meaning that lower values do not necessarily indicate processes that started to run earlier.

In Unix-like operating systems, new processes are created by the fork system call. The PID is returned to the parent enabling it to refer to the child in further function calls. The parent may, for example, wait for the child to terminate with the waitpid function, or terminate the process with kill. There are two tasks with specially distinguished process IDs: swapper or sched has process ID 0 and is responsible for paging, and is actually part of the kernel rather than a normal user-mode process.

A blog about Linux, programming, and other ideas. Here is a short explanation of these Linux terms. What is the PPID? Share this: Twitter Facebook. Like this: Like Loading Comments 0 Leave a comment. Leave a Reply Cancel reply Enter your comment here Fill in your details below or click an icon to log in:. Email required Address never made public. Name required. Categories books 5 Lessons 25 linux other 12 Programming 30 Trivia Follow Following. In this article, we will look at how to find a process name by its process identification number PID.

Before we dive into the actual solution, let us briefly talk about how processes are created and identified by Linux. Every time a user or the system Linux launches a program, the kernel will create a process. A process holds execution details of the program in memory such as its input and output data, variables and so on.

Importantly, since Linux is a multitasking operating system, it executes several programs simultaneously, and this means each process process must be identified specifically. The kernel identifies each process using a process ID PID , a every instance of process must have a unique PID from other processes which is assigned when the process is invoked, to avoid any execution errors.

From the screenshot above, the numbered directories store information files about the processes in execution, where each number corresponds to a PID. You can monitor processes and their PIDs using traditional Linux commands such as ps , top and relatively new glances command plus many more as in the examples below:.

Monitor Linux processes using traditional top command.