diff --git a/man/udev.xml b/man/udev.xml
index 9b97ee63d9..350ebcf5a2 100644
--- a/man/udev.xml
+++ b/man/udev.xml
@@ -280,13 +280,17 @@
PROGRAM
- Execute a program to determine whether there
- is a match; the key is true if the program returns
- successfully. The device properties are made available to the
- executed program in the environment. The program's standard output
- is available in the RESULT key.
- This can only be used for very short-running foreground tasks. For details,
- see RUN.
+ Execute a program to determine whether there is a match; the key is true if the program
+ returns successfully. The device properties are made available to the executed program in the
+ environment. The program's standard output is available in the RESULT
+ key.
+
+ This can only be used for very short-running foreground tasks. For details, see
+ RUN.
+
+ Note that multiple PROGRAM keys may be specified in one rule, and
+ =, :=, and += have the same effect as
+ ==.
@@ -429,9 +433,14 @@
RUN{type}
- Add a program to the list of programs to be executed after
- processing all the rules for a specific event, depending on
- type:
+ Specify a program to be executed after processing of all the rules for the event. With
+ +=, this invocation is added to the list, and with = or
+ :=, it replaces any previous contents of the list. Please note that both
+ program and builtin types described below use a single
+ list, so clearing the list with := and = affects both
+ types.
+
+ type may be:program
@@ -452,21 +461,21 @@
- The program name and following arguments are separated by spaces.
- Single quotes can be used to specify arguments with spaces.
- This can only be used for very short-running foreground tasks. Running an
- event process for a long period of time may block all further events for
- this or a dependent device.
- Starting daemons or other long-running processes is not appropriate
- for udev; the forked processes, detached or not, will be unconditionally
- killed after the event handling has finished.
- Note that running programs that access the network or mount/unmount
- filesystems is not allowed inside of udev rules, due to the default sandbox
- that is enforced on systemd-udevd.service.
- Please also note that := and = are clearing
- both, program and builtin commands.
- In order to activate long-running processes from udev rules, provide a service unit, and
- pull it in from a udev device using the SYSTEMD_WANTS device property. See
+
+ The program name and following arguments are separated by spaces. Single quotes can be
+ used to specify arguments with spaces.
+
+ This can only be used for very short-running foreground tasks. Running an event process for
+ a long period of time may block all further events for this or a dependent device.
+
+ Note that running programs that access the network or mount/unmount filesystems is not
+ allowed inside of udev rules, due to the default sandbox that is enforced on
+ systemd-udevd.service.
+
+ Starting daemons or other long-running processes is not allowed; the forked processes,
+ detached or not, will be unconditionally killed after the event handling has finished. In order
+ to activate long-running processes from udev rules, provide a service unit and pull it in from a
+ udev device using the SYSTEMD_WANTS device property. See
systemd.device5
for details.
@@ -489,8 +498,9 @@
IMPORT{type}
- Import a set of variables as device properties,
- depending on type:
+ Import a set of variables as device properties, depending on
+ type:
+
program
@@ -542,8 +552,14 @@
- This can only be used for very short-running foreground tasks. For details
- see .
+
+ This can only be used for very short-running foreground tasks. For details see
+ .
+
+ Note that multiple IMPORT{} keys may be specified in one rule, and
+ =, :=, and += have the same effect as
+ ==. The key is true if the import is successful, unless !=
+ is used as the operator which causes the key to be true if the import failed.
@@ -633,9 +649,8 @@
,
- The kernel number for this device. For example,
- sda3 has kernel number 3.
-
+ The kernel number for this device. For example, sda3 has kernel number
+ 3.