March 2002
Beginner
504 pages
10h 47m
English
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Starting a Process
Whenever you issue a command in UNIX, it creates, or starts, a new process on your behalf. When you tried out the ls command to list directory contents in Chapter 4, “Working with Directories,” the system started a process, the ls command, for you.
UNIX tracks processes through a five-digit ID number known as the pid (short for process identifier). Each process in the system has a unique pid between 1 and 32,767. Pids eventually repeat when all the possible numbers are used. Two processes with the same pid cannot be concurrently executed on the system.
Foreground Processes
By default, every process runs in the foreground. It gets its input from the keyboard and sends its output to the screen. You can see this happen with the ...
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I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
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