daemons/become_daemon.h

This is daemons/become_daemon.h (Listing 37-1, page 770), an example from the book, The Linux Programming Interface.

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Cover of The Linux Programming Interface

+/* become_daemon.h
+
+   Header file for become_daemon.c.
+*/
 #ifndef BECOME_DAEMON_H             /* Prevent double inclusion */
 #define BECOME_DAEMON_H
 
 /* Bit-mask values for 'flags' argument of becomeDaemon() */
 
 #define BD_NO_CHDIR           01    /* Don't chdir("/") */
 #define BD_NO_CLOSE_FILES     02    /* Don't close all open files */
 #define BD_NO_REOPEN_STD_FDS  04    /* Don't reopen stdin, stdout, and
                                        stderr to /dev/null */
 #define BD_NO_UMASK0         010    /* Don't do a umask(0) */
 
 #define BD_MAX_CLOSE  8192          /* Maximum file descriptors to close if
                                        sysconf(_SC_OPEN_MAX) is indeterminate */
 
 int becomeDaemon(int flags);
 
 #endif

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