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diff --git a/spawnd.8 b/spawnd.8 new file mode 100644 index 0000000..fc97498 --- /dev/null +++ b/spawnd.8 @@ -0,0 +1,196 @@ +.Dd August 13, 2020 +.Dt SPAWND 8 +.Os +. +.Sh NAME +.Nm spawnd +.Nd process supervisor +. +.Sh SYNOPSIS +.Nm +.Op Fl d +.Op Fl C Ar path +.Op Fl c Ar control +.Op Fl f Ar spawntab +.Op Fl g Ar group +.Op Fl p Ar pidfile +.Op Fl s Ar stopexits +.Op Fl t Ar interval +.Op Fl u Ar user +. +.Sh DESCRIPTION +The +.Nm +daemon +is a supervisor for processes +with the following behavior: +.Bl -enum +.It +The process runs in the foreground, +not as a daemon. +.It +The process logs to standard output or standard error. +.It +The process handles errors by exiting +and expects to be restarted. +.It +The process indicates its reason for exiting with +.Xr sysexits 3 . +.El +. +.Pp +The +.Nm +daemon spawns processes for a list of +.Em services , +redirects their output to syslog, +and restarts the processes when they exit +according to their exit status. +Exponential backoff is applied to restarts. +. +.Pp +The list of services is defined in a +.Xr spawntab 5 +file. +The services managed by +.Nm +can be controlled +through a named pipe. +The +.Xr spawn 8 +utility is a wrapper +around the named pipe, +and its manual page +describes the control command format. +. +.Pp +The arguments are as follows: +.Bl -tag -width Ds +.It Fl C Ar path +Change directory to +.Ar path +before starting services. +By default the working directory is +.Pa / . +. +.It Fl c Ar control +Set the path of the named pipe +used for control. +. +.It Fl d +Do not run as a daemon. +. +.It Fl f Ar spawntab +Set the path of the +.Xr spawntab 5 +file. +. +.It Fl g Ar group +Change group to +.Ar group +before starting services. +If +.Fl u +is used, +the default group is the user's group. +. +.It Fl p Ar pidfile +Write the PID of the +.Nm +process to +.Ar pidfile . +. +.It Fl s Ar stopexits +Set the list of exit statuses +for which a restart will not be attempted. +The +.Ar stopexits +argument is a comma-separated list of integers. +The default list contains the values of +.Dv EX_USAGE , +.Dv EX_DATAERR , +.Dv EX_NOINPUT , +.Dv EX_OSFILE , +.Dv EX_CANTCREAT , +.Dv EX_CONFIG +defined in +.Xr sysexits 3 , +as well as 127. +. +.It Fl t Ar interval +Set the initial interval between restarts +in milliseconds. +The default interval is 1000. +. +.It Fl u Ar user +Change user to +.Ar user +before starting services. +.El +. +.Pp +When the +.Nm +daemon receives the +.Dv HUP +signal, +the +.Xr spawntab 5 +file is reloaded. +Modified services +are not automatically restarted, +newly added services +are not automatically started, +and removed services +are not automatically stopped. +. +.Pp +When the +.Nm +daemon receives the +.Dv TERM +signal, +the control named pipe is closed, +all services are stopped, +and +.Nm +exits. +. +.Sh ENVIRONMENT +Services are started +with empty environments +apart from the following: +.Bl -tag -width Ds +.It Ev LOGNAME , Ev USER +Set to the name of the user specified by +.Fl u . +.It Ev HOME +Set to the home directory of the user specified by +.Fl u . +.It Ev SHELL +Set to +.Pa /bin/sh . +.It Ev PATH +Set to the system default defined by +.Dv _PATH_DEFPATH +in +.In paths.h . +.El +. +.Sh FILES +.Bl -tag -width Ds +.It Pa /usr/local/etc/spawntab +The default path of the +.Xr spawntab 5 +file. +.It Pa /var/run/spawnd.pipe +The default path of the named pipe +used for control. +.El +. +.Sh SEE ALSO +.Xr spawntab 5 , +.Xr spawn 8 +. +.Sh AUTHORS +.An June Bug Aq Mt june@causal.agency |