Unformatted text preview: nal to be sent to every process in process group PID. For example,
unix> kill -9 -15213 sends a SIGKILL signal to every process in process group 15213. Sending Signals From the Keyboard
Unix shells use the abstraction of a job to represent the processes that are created as a result of evaluating a single command line. At any point in time, there is at most one foreground job and zero or more background jobs. For example, typing
unix> ls | sort creates a foreground job consisting of two processes connected by a Unix pipe: one running the ls program, the other running the sort program. The shell creates a separate process group for each job. Typically, the process group ID is taken from one of the parent processes in the job. For example, Figure 8.24 shows a shell with one foreground job and two background jobs. The parent process in the foreground job has a PID of 20 and a process group ID of 20. The parent process has created two children, each of which are also members of process group 20. Typing ctrl-c at the ke...
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