Five programming rules for the daemon in linux

Five programming rules for the daemon in linux-general Linux technology-Linux programming and kernel information. The following is a detailed description. (1) create a child process and exit the parent process:
Call fork first, and then exit the parent process. At this time, the child process is an orphan process, and all orphan processes on linux are managed by the init 1 process.
(2) Call setsid to create a new session and act as the group leader
(3) change the current directory to the root directory chdir ("/")
(4) resetting the File Permission mask umask (0 );
(5) disable unnecessary file descriptors
As long as you follow these rules, it will be smooth.
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