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36 .Op Fl m Ar mount-point
42 utility provides an interface to manipulate properties of
48 argument determines the context for
49 the rest of the arguments.
51 most of the commands related to the rule subsystem must be preceded by the
54 The following flags are common to all keywords:
56 .It Fl m Ar mount-point
59 which is expected to be a
62 If this option is not specified,
70 rule subsystem provides a way for the administrator of a system to control
71 the attributes of DEVFS nodes.
72 .\" XXX devfs node? entry? what?
73 Each DEVFS mount-point has a
77 When a device driver creates a new node,
78 all the rules in the ruleset associated with each mount-point are applied
79 (see below) before the node becomes visible to the userland.
80 This permits the administrator to change the properties,
81 including the visibility,
83 For example, one might want to hide all disk nodes in a
87 Rule manipulation commands follow the
90 The following flags are common to all of the rule manipulation commands:
93 Operate on the ruleset with the number
95 If this is not specified,
96 the commands operate on the ruleset currently associated with the
97 specified mount-point.
100 The following commands are recognized:
102 .It Cm rule add Oo Ar rulenum Oc Ar rulespec
103 Add the rule described by
107 The rule has the number
109 if it is explicitly specified;
110 otherwise, the rule number is automatically determined by the kernel.
111 .It Cm rule apply Ar rulenum | rulespec
114 or the rule described by
119 have their conditions checked against all nodes
120 in the mount-point and the actions taken if they match.
122 Apply all the rules in the ruleset to the mount-point
123 (see above for the definition of
125 .It Cm rule del Ar rulenum
130 Delete all rules from the ruleset.
131 .It Cm rule show Op Ar rulenum
132 Display the rule number
134 or all the rules in the ruleset.
135 The output lines (one line per rule) are expected to be valid
138 Report the numbers of existing rulesets.
139 .It Cm ruleset Ar ruleset
142 as the current ruleset for the mount-point.
144 .Ss Rule Specification
145 Rules have two parts: the conditions and the actions.
146 The conditions determine which DEVFS nodes the rule matches
147 and the actions determine what should be done when a rule matches a node.
148 For example, a rule can be written that sets the GID to
150 for all devices of type tape.
151 If the first token of a rule specification is a single dash
153 rules are read from the standard input and the rest of the specification
156 The following conditions are recognized.
157 Conditions are ANDed together when matching a device;
158 if OR is desired, multiple rules can be written.
160 .It Cm path Ar pattern
161 Matches any node with a path that matches
163 which is interpreted as a
166 .It Cm type Ar devtype
167 Matches any node that is of type
170 .Cm disk , mem , tape
175 The following actions are recognized.
176 Although there is no explicit delimiter between conditions and actions,
177 they may not be intermixed.
180 Set the GID of the node to
182 which may be a group name
188 Nodes may later be revived manually with
193 Hiding a directory node effectively hides all of its child nodes.
194 .It Cm include Ar ruleset
195 Apply all the rules in ruleset number
198 This does not necessarily result in any changes to the node
199 (e.g., if none of the rules in the included ruleset match).
200 Include commands in the referenced
203 .It Cm mode Ar filemode
206 which is interpreted as in
211 which may be a user name
217 If the node resides in a subdirectory,
218 all parent directory nodes must be visible to be able to access the node.
220 .Sh IMPLEMENTATION NOTES
221 Rulesets are created by the kernel at the first reference
222 and destroyed when the last reference disappears.
223 E.g., a ruleset is created when a rule is added to it or when it is set
224 as the current ruleset for a mount-point, and
225 a ruleset is destroyed when the last rule in it is deleted
226 and no other references to it exist
227 (i.e., it is not included by any rules and it is not the current ruleset
228 for any mount-point).
230 Ruleset number 0 is the default ruleset for all new mount-points.
231 It is always empty, cannot be modified or deleted, and does not show up
235 Rules and rulesets are unique to the entire system,
236 not a particular mount-point.
239 will return the same information regardless of the mount-point specified with
241 The mount-point is only relevant when changing what its current ruleset is
242 or when using one of the apply commands.
244 .Bl -tag -width "Pa /usr/share/examples/etc/devfs.conf" -compact
245 .It Pa /etc/defaults/devfs.rules
249 .It Pa /etc/devfs.rules
253 Rulesets in here override those in
254 .Pa /etc/defaults/devfs.rules
255 with the same ruleset number, otherwise the two files are effectively merged.
256 .It Pa /etc/devfs.conf
260 .It Pa /usr/share/examples/etc/devfs.conf
266 When the system boots,
267 the only ruleset that exists is ruleset number 0;
268 since the latter may not be modified, we have to create another ruleset
270 Note that since most of the following examples do not specify
272 the operations are performed on
274 (this only matters for things that might change the properties of nodes).
276 Specify that ruleset 10 should be the current ruleset for
278 (if it does not already exist, it is created):
280 .Dl "devfs ruleset 10"
282 Add a rule that causes all nodes that have a path that matches
286 to have the file mode 666 (read and write for all).
287 Note that if any such nodes already exist, their mode will not be changed
288 unless this rule (or ruleset) is explicitly applied (see below).
291 be changed if the node is created
296 module is loaded after the above rule is added):
298 .Dl "devfs rule add path speaker mode 666"
300 Apply all the rules in the current ruleset to all the existing nodes.
301 E.g., if the below rule was added after
304 this command will cause its file mode to be changed to 666
305 as prescribed by the rule:
307 .Dl "devfs rule applyset"
309 For all devices with a path that matches
311 set the file mode to 660 and the GID to
313 This permits users in the
318 (quoting the argument to
320 is often necessary to disable the shell's globbing features):
322 .Dl devfs rule add path "snp*" mode 660 group snoopers
324 Add a rule to ruleset number 20.
325 Since this ruleset is not the current ruleset for any mount-points,
326 this rule is never applied automatically (unless ruleset 20 becomes
327 a current ruleset for some mount-point at a later time):
329 .Dl "devfs rule -s 20 add type disk group wheel"
331 Explicitly apply all rules in ruleset number 20 to the DEVFS mount on
333 It does not matter that ruleset 20 is not the current ruleset for that
334 mount-point; the rules are still applied:
336 .Dl "devfs -m /my/jail/dev rule -s 20 applyset"
338 Since the following rule has no conditions, the action
340 will be applied to all nodes:
342 .Dl "devfs rule apply hide"
344 Since hiding all nodes is not very useful, we can undo it.
345 The following applies
348 causing them to reappear:
350 .Dl "devfs rule apply unhide"
352 Add all the rules from the file
356 .Dl "devfs rule -s 10 add - < my_rules"
358 The below copies all the rules from ruleset 20 into ruleset 10.
359 The rule numbers are preserved,
360 but ruleset 10 may already have rules with non-conflicting numbers
361 (these will be preserved).
365 this feature can be used to copy rulesets:
367 .Dl "devfs rule -s 20 show | devfs rule -s 10 add -"
381 utility first appeared in
projects / FreeBSD / stable / 10.git / blob