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daemon(8) [freebsd man page]

DAEMON(8)						    BSD System Manager's Manual 						 DAEMON(8)

NAME
daemon -- run detached from the controlling terminal SYNOPSIS
daemon [-cfr] [-p child_pidfile] [-P supervisor_pidfile] [-u user] command arguments ... DESCRIPTION
The daemon utility detaches itself from the controlling terminal and executes the program specified by its arguments. Privileges may be low- ered to the specified user. The options are as follows: -c Change the current working directory to the root (``/''). -f Redirect standard input, standard output and standard error to /dev/null. -p child_pidfile Write the ID of the created process into the child_pidfile using the pidfile(3) functionality. The program is executed in a spawned child process while the daemon waits until it terminates to keep the child_pidfile locked and removes it after the process exits. The child_pidfile owner is the user who runs the daemon regardless of whether the -u option is used or not. -P supervisor_pidfile Write the ID of the daemon process into the supervisor_pidfile using the pidfile(3) functionality. The program is executed in a spawned child process while the daemon waits until it terminates to keep the supervisor_pidfile locked and removes it after the process exits. The supervisor_pidfile owner is the user who runs the daemon regardless of whether the -u option is used or not. -r Supervise and restart the program if it has been terminated. -u user Login name of the user to execute the program under. Requires adequate superuser privileges. If the -p, -P or -r option is specified the program is executed in a spawned child process. The daemon waits until it terminates to keep the pid file(s) locked and removes them after the process exits or restarts the program. In this case if the monitoring daemon receives software termination signal (SIGTERM) it forwards it to the spawned process. Normally it will cause the child to exit, remove the pidfile(s) and then terminate. The -P option is useful combined with the -r option as supervisor_pidfile contains the ID of the supervisor not the child. This is especially important if you use -r in an rc script as the -p option will give you the child's ID to signal when you attempt to stop the service, causing daemon to restart the child. EXIT STATUS
The daemon utility exits 1 if an error is returned by the daemon(3) library routine, 2 if child_pidfile or supervisor_pidfile is requested, but cannot be opened, 3 if process is already running (pidfile exists and is locked), otherwise 0. DIAGNOSTICS
If the command cannot be executed, an error message is displayed on standard error unless the -f flag is specified. SEE ALSO
setregid(2), setreuid(2), daemon(3), exec(3), pidfile(3), termios(4), tty(4) HISTORY
The daemon utility first appeared in FreeBSD 4.7. BSD
September 13, 2013 BSD

Check Out this Related Man Page

ISCSID(8)						    BSD System Manager's Manual 						 ISCSID(8)

NAME
iscsid -- iSCSI initiator daemon SYNOPSIS
iscsid [-P pidfile] [-d] [-l loglevel] [-m maxproc] [-t seconds] DESCRIPTION
The iscsid daemon is responsible for performing the Login Phase of iSCSI connections, as well as performing SendTargets discovery. Upon startup, the iscsid daemon opens the iSCSI initiator device file and waits for kernel requests. iscsid does not use any configuration files. All needed information is supplied by the kernel. When the iscsid daemon is not running, already established iSCSI connections continue to work. However, establishing new connections, or recovering existing ones in case of connection error, is not possible. The following options are available: -P pidfile Specify alternative location of a file where main process PID will be stored. The default location is /var/run/iscsid.pid. -d Debug mode. The server sends verbose debug output to standard error, and does not put itself in the background. The server will also not fork and will exit after processing one connection. This option is only intended for debugging the initiator. -l loglevel Specifies debug level. The default is 0. -m maxproc Specifies limit for concurrently running child processes handling connections. The default is 30. Setting it to 0 disables the limit. -t seconds Specifies timeout for login session, after which the connection will be forcibly terminated. The default is 60. Setting it to 0 disables the timeout. FILES
/dev/iscsi The iSCSI initiator device file. /var/run/iscsid.pid The default location of the iscsid PID file. EXIT STATUS
The iscsid utility exits 0 on success, and >0 if an error occurs. SEE ALSO
iscsi(4), iscsictl(8) HISTORY
The iscsid command appeared in FreeBSD 10.0. AUTHORS
The iscsid utility was developed by Edward Tomasz Napierala <trasz@FreeBSD.org> under sponsorship from the FreeBSD Foundation. BSD
September 12, 2014 BSD

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