path: root/doc/dropnroll.8

'\" t
.\"     Title: dropnroll
.\"    Author: [see the "AUTHORS" section]
.\" Generator: DocBook XSL Stylesheets v1.78.1 <http://docbook.sf.net/>
.\"      Date: 09/23/2015
.\"    Manual: \ \&
.\"    Source: \ \&
.\"  Language: English
.\"
.TH "DROPNROLL" "8" "09/23/2015" "\ \&" "\ \&"
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.SH "NAME"
dropnroll \- drop\*(Aqn\*(Aqroll daemon
.SH "SYNOPSIS"
.sp
.nf
\fBdropnroll\fR
  [ \fB\-h|\-\-help\fR ]
  [ \fB\-D|\-\-nodaemonize\fR ]
  [ \fB\-u|\-\-username\fR <username> ]
  [ \fB\-g|\-\-groupname\fR <groupname> ]
  [ \fB\-C|\-\-chroot\fR <path> ]
  [ \fB\-P|\-\-write\-pid\fR <filename> ]
  [ \fB\-L|\-\-log\fR <target>:<level>[,<param1>[,<param2>[\&.\&.]]] ]
  [ \fB\-U|\-\-debug\fR ]
  [ \fB\-s|\-\-command\-sock\fR <unix sock> ]
  [ \fB\-x|\-\-script\fR <script> ]
  [ \fB\-m|\-\-max\-children\fR <#of children> ]
  [ \fB\-p|\-\-children\-policy\fR (defer|drop|kill\-oldest) ]
  [ \fB\-r|\-\-children\-min\-runtime\fR <secs> ]
  [ \fB\-d|\-\-dir\fR <path> ]
.fi
.SH "DESCRIPTION"
.sp
\fBdropnroll\fR is a small daemon which can be used to watch one or more directories for new files\&. When a new file is detected an external program will get started\&. Additional directories can be added to the daemon\(cqs watch list using a simple unix socket based command interface\&.
.SH "OPTIONS"
.sp
The following options can be passed to the \fBdropnroll\fR daemon:
.PP
\fB\-D, \-\-nodaemonize\fR
.RS 4
This option instructs
\fBdropnroll\fR
to run in foreground instead of becoming a daemon which is the default\&.
.RE
.PP
\fB\-u, \-\-username \fR\fB\fI<username>\fR\fR
.RS 4
run as this user\&. If no group is specified (\fB\-g\fR) the default group of the user is used\&. The default is to not drop privileges\&.
.RE
.PP
\fB\-g, \-\-groupname \fR\fB\fI<groupname>\fR\fR
.RS 4
run as this group\&. If no username is specified (\fB\-u\fR) this gets ignored\&. The default is to not drop privileges\&.
.RE
.PP
\fB\-C, \-\-chroot \fR\fB\fI<path>\fR\fR
.RS 4
Instruct
\fBdropnroll\fR
to run in a chroot jail\&. The default is to not run in chroot\&.
.RE
.PP
\fB\-P, \-\-write\-pid \fR\fB\fI<filename>\fR\fR
.RS 4
Instruct
\fBdropnroll\fR
to write it\(cqs pid to this file\&. The default is to not create a pid file\&.
.RE
.PP
\fB\-L, \-\-log \fR\fB\fI<target>:<level>[,<param1>[,<param2>[\&.\&.]]]\fR\fR
.RS 4
add log target to logging system\&. This can be invoked several times in order to log to different targets at the same time\&. Every target hast its own log level which is a number between 0 and 5\&. Where 0 means disabling log and 5 means debug messages are enabled\&.

The file target can be used more the once with different levels\&. If no target is provided at the command line a single target with the config
\fBsyslog:3,dropnroll,daemon\fR
is added\&.

The following targets are supported:
.PP
\fIsyslog\fR
.RS 4
log to syslog daemon, parameters <level>[,<logname>[,<facility>]]
.RE
.PP
\fIfile\fR
.RS 4
log to file, parameters <level>[,<path>]
.RE
.PP
\fIstdout\fR
.RS 4
log to standard output, parameters <level>
.RE
.PP
\fIstderr\fR
.RS 4
log to standard error, parameters <level>
.RE
.RE
.PP
\fB\-U, \-\-debug\fR
.RS 4
This option instructs
\fBdropnroll\fR
to run in debug mode\&. It implicits
\fB\-D\fR
(don\(cqt daemonize) and adds a log target with the configuration
\fIstdout:5\fR
(logging with maximum level)\&. In future releases there might be additional output when this option is supplied\&.
.RE
.PP
\fB\-s|\-\-command\-sock \fR\fB\fI<unix sock>\fR\fR
.RS 4
\fBdropnroll\fR
will listen on this unix socket for incoming commands\&. See next chapter for details\&. If there are directories specified using the
\fB\-\-dir\fR
option and this is kept empty the command socket is deactivated\&. If no directories are added it defaults to /var/run/dropnroll/cmd\&.sock
.RE
.PP
\fB\-x|\-\-script \fR\fB\fI<script>\fR\fR
.RS 4
The script which should be called when a new file is found\&. The following parameter are passed to the scipt:
.PP
\fI<path>\fR
.RS 4
the path to the folder containing the new file
.RE
.PP
\fI<filename>\fR
.RS 4
the name of the new file relative to <path>
.RE
.PP
\fI<filesize>\fR
.RS 4
the size of the file right after the event was received, this can be used to determine wheter the file is complete\&. The script should consider a file to be complete when it size doesn\(cqt change 3\-5seconds after the event got received\&.
.RE
.RE
.PP
\fB\-m|\-\-max\-children \fR\fB\fI<#of children>\fR\fR
.RS 4
Limits the total concurrent executions of
\fB\-x|\-\-script\fR\&. A value of 0 means no limit\&.
.RE
.PP
\fB\-p|\-\-children\-policy \fR\fB\fI(defer|drop|kill\-oldest)\fR\fR
.RS 4
Specifies what
\fBdropnroll\fR
should do when the client limit has been reached:
.PP
\fIdefer\fR
.RS 4
defer the execution of
\fB\-\-script\fR
until the number of children is below the limit
.RE
.PP
\fIdrop\fR
.RS 4
ingore the new file and don\(cqt call
\fB\-\-script\fR
.RE
.PP
\fIkill\-oldest\fR
.RS 4
kill the oldest child (using SIGKILL)
.RE
.RE
.PP
\fB\-r|\-\-children\-min\-runtime \fR\fB\fI<secs>\fR\fR
.RS 4
For the kill\-oldest policy this sets the minimum number of seconds a child needs to run before it can be killed\&.
.RE
.PP
\fB\-d|\-\-dir \fR\fB\fI<path>\fR\fR
.RS 4
Add
\fI<path>\fR
to the watch list\&. This can be invoked serveral times\&.
.RE
.SH "COMMAND INTERFACE"
.sp
\fBdropnroll\fR is listening for incoming commands at the unix socket speciefied by the \fB\-s|\-\-command\-sock\fR parameter\&. You can connect to this socket for example using socat:
.sp
.if n \{\
.RS 4
.\}
.nf
# socat UNIX\-CONNECT:/var/run/dropnroll/dropnroll\&.sock STDIO
.fi
.if n \{\
.RE
.\}
.sp
All commands have to end with \fI\en\fR\&. The following commands are supported:
.PP
\fBadd <path>\fR
.RS 4
Add a path to the list of directories to be watched\&. If the command succeds nothing is returned\&. In case of an error a string of the form "Error: <reason>\en" is returned\&.
.RE
.PP
\fBremove <path>\fR
.RS 4
Remove the path from the list of directories\&. If the command succeds nothing is returned\&. In case of an error a string of the form "Error: <reason>\en" is returned\&.
.RE
.PP
\fBstatus\fR
.RS 4
Returns the complete list of all directories of the watch list\&.
.RE
.PP
\fBlisten (request|status|none)\fR
.RS 4
Add the client to the status and or request listeners\&. When no parameter is passed to this command the client listens to all messages\&. A status listener gets a list of all directories whenever somebody else adds or removes a path to the watch list\&. It also receives the list when somebody sends a status command to the daemon\&. A request listener also receives add and remove requests by other clients connected to the command interface\&.
.RE
.PP
\fBlog <text>\fR
.RS 4
Print <text> to the logtargets of the daemon\&.
.RE
.SH "BUGS"
.sp
Most likely there are some bugs in \fBdropnroll\fR\&. If you find a bug, please let the developers know at equinox@spreadspace\&.org\&. Of course, patches are preferred\&.
.SH "AUTHORS"
.sp
Christian Pointner <equinox@spreadspace\&.org>
.SH "COPYING"
.sp
Copyright (C) 2009\-2015 Christian Pointner\&. This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or any later version\&.