# systemd.path

## NAME



           systemd.path - Path unit configuration
    


## SYNOPSIS



           _path_.path
    


## DESCRIPTION



           A unit configuration file whose name ends in ".path" encodes
           information about a path monitored by systemd, for path-based
           activation.
    
           This man page lists the configuration options specific to this
           unit type. See systemd.unit(5) for the common options of all unit
           configuration files. The common configuration items are configured
           in the generic [Unit] and [Install] sections. The path specific
           configuration options are configured in the [Path] section.
    
           For each path file, a matching unit file must exist, describing
           the unit to activate when the path changes. By default, a service
           by the same name as the path (except for the suffix) is activated.
           Example: a path file foo.path activates a matching service
           foo.service. The unit to activate may be controlled by _Unit=_ (see
           below).
    
           Internally, path units use the inotify(7) API to monitor file
           systems. Due to that, it suffers by the same limitations as
           inotify, and for example cannot be used to monitor files or
           directories changed by other machines on remote NFS file systems.
    
           When a service unit triggered by a path unit terminates
           (regardless whether it exited successfully or failed), monitored
           paths are checked immediately again, and the service accordingly
           restarted instantly. As protection against busy looping in this
           trigger/start cycle, a start rate limit is enforced on the service
           unit, see _StartLimitIntervalSec=_ and _StartLimitBurst=_ in
           systemd.unit(5). Unlike other service failures, the error
           condition that the start rate limit is hit is propagated from the
           service unit to the path unit and causes the path unit to fail as
           well, thus ending the loop.
    


## AUTOMATIC DEPENDENCIES



       **Implicit Dependencies**
           The following dependencies are implicitly added:
    
           •   If a path unit is beneath another mount unit in the file
               system hierarchy, both a requirement and an ordering
               dependency between both units are created automatically.
    
           •   An implicit _Before=_ dependency is added between a path unit
               and the unit it is supposed to activate.
    
       **Default Dependencies**
           The following dependencies are added unless _DefaultDependencies=no_
           is set:
    
           •   Path units will automatically have dependencies of type
               _Before=_ on paths.target, dependencies of type _After=_ and
               _Requires=_ on sysinit.target, and have dependencies of type
               _Conflicts=_ and _Before=_ on shutdown.target. These ensure that
               path units are terminated cleanly prior to system shutdown.
               Only path units involved with early boot or late system
               shutdown should disable _DefaultDependencies=_ option.
    


## OPTIONS



           Path unit files may include [Unit] and [Install] sections, which
           are described in systemd.unit(5).
    
           Path unit files must include a [Path] section, which carries
           information about the path or paths it monitors. The options
           specific to the [Path] section of path units are the following:
    
           _PathExists=_ , _PathExistsGlob=_ , _PathChanged=_ , _PathModified=_ ,
           _DirectoryNotEmpty=_
               Defines paths to monitor for certain changes: _PathExists=_ may
               be used to watch the mere existence of a file or directory. If
               the file specified exists, the configured unit is activated.
               _PathExistsGlob=_ works similarly, but checks for the existence
               of at least one file matching the globbing pattern specified.
               _PathChanged=_ may be used to watch a file or directory and
               activate the configured unit whenever it changes. It is not
               activated on every write to the watched file but it is
               activated if the file which was open for writing gets closed.
               _PathModified=_ is similar, but additionally it is activated
               also on simple writes to the watched file.  _DirectoryNotEmpty=_
               may be used to watch a directory and activate the configured
               unit whenever it contains at least one file.
    
               The arguments of these directives must be absolute file system
               paths.
    
               Multiple directives may be combined, of the same and of
               different types, to watch multiple paths. If the empty string
               is assigned to any of these options, the list of paths to
               watch is reset, and any prior assignments of these options
               will not have any effect.
    
               If a path already exists (in case of _PathExists=_ and
               _PathExistsGlob=_) or a directory already is not empty (in case
               of _DirectoryNotEmpty=_) at the time the path unit is activated,
               then the configured unit is immediately activated as well.
               Something similar does not apply to _PathChanged=_ and
               _PathModified=_.
    
               If the path itself or any of the containing directories are
               not accessible, **systemd** will watch for permission changes and
               notice that conditions are satisfied when permissions allow
               that.
    
               Note that files whose name starts with a dot (i.e. hidden
               files) are generally ignored when monitoring these paths.
    
           _Unit=_
               The unit to activate when any of the configured paths changes.
               The argument is a unit name, whose suffix is not ".path". If
               not specified, this value defaults to a service that has the
               same name as the path unit, except for the suffix. (See
               above.) It is recommended that the unit name that is activated
               and the unit name of the path unit are named identical, except
               for the suffix.
    
           _MakeDirectory=_
               Takes a boolean argument. If true, the directories to watch
               are created before watching. This option is ignored for
               _PathExists=_ settings. Defaults to **false**.
    
           _DirectoryMode=_
               If _MakeDirectory=_ is enabled, use the mode specified here to
               create the directories in question. Takes an access mode in
               octal notation. Defaults to **0755**.
    
           _TriggerLimitIntervalSec=_ , _TriggerLimitBurst=_
               Configures a limit on how often this path unit may be
               activated within a specific time interval. The
               _TriggerLimitIntervalSec=_ may be used to configure the length
               of the time interval in the usual time units "us", "ms", "s",
               "min", "h", ... and defaults to 2s. See systemd.time(7) for
               details on the various time units understood. The
               _TriggerLimitBurst=_ setting takes a positive integer value and
               specifies the number of permitted activations per time
               interval, and defaults to 200. Set either to 0 to disable any
               form of trigger rate limiting. If the limit is hit, the unit
               is placed into a failure mode, and will not watch the paths
               anymore until restarted. Note that this limit is enforced
               before the service activation is enqueued.
    
               Added in version 250.
    
           Check systemd.unit(5), systemd.exec(5), and systemd.kill(5) for
           more settings.
    


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