diff options
| author | Daniel Drake <dsd@laptop.org> | 2011-07-20 18:25:03 +0100 |
|---|---|---|
| committer | Peter Hutterer <peter.hutterer@who-t.net> | 2011-07-22 09:55:37 +1000 |
| commit | 8a10dfe3b7bc53b319107de89434922a2c79ef94 (patch) | |
| tree | 4bc3f50a848f0b4161a38c1775e38cfb84d08701 /evtest.txt | |
| parent | 6015b4c4cf0efeb845673c37d80f3049e86c04a1 (diff) | |
Add one-shot query functionality
Add functionality to query evdev state of a specific key, switch, button,
LED or sound event. This is useful in programs such as powerd
(http://wiki.laptop.org/go/Powerd) which need to query things like the
state of the laptop lid switch from shell code.
Original capture-mode functionality is left unchanged and is still
activated by default. New usage modes are explained in the man page.
Signed-off-by: Daniel Drake <dsd@laptop.org>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Diffstat (limited to 'evtest.txt')
| -rw-r--r-- | evtest.txt | 33 |
1 files changed, 28 insertions, 5 deletions
@@ -4,17 +4,33 @@ EVTEST(1) NAME ---- - evtest - Input device event monitor + evtest - Input device event monitor and query tool SYNOPSIS -------- - evtest "/dev/input/eventX" + evtest /dev/input/eventX + + evtest --query /dev/input/eventX <type> <value> DESCRIPTION ----------- -evtest displays information on the input device specified on the command -line, including all the events supported by the device. It then monitors the -device and displays all the events layer events generated. +The first invocation type displayed above ("capture mode") causes evtest to +display information about the specified input device, including all the events +supported by the device. It then monitors the device and displays all the +events layer events generated. + +In the second invocation type ("query mode"), evtest performs a one-shot query +of the state of a specific key *value* of an event *type*. + +*type* is one of: *EV_KEY*, *EV_SW*, *EV_SND*, *EV_LED* (or the numerical value) + +*value* can be either a decimal representation (e.g. 44), hex +(e.g. 0x2c), or the constant name (e.g. KEY_Z) of the key/switch/sound/LED +being queried. + +If the state bit is set (key pressed, switch on, ...), evtest exits with +code 0. If the state bit is unset (key depressed, switch off, ...), evtest +exits with code 10. No other output is generated. evtest needs to be able to read from the device; in most cases this means it must be run as root. @@ -32,6 +48,13 @@ when debugging a synaptics device from within X. VT switching to a TTY or shutting down the X server terminates this grab and synaptics devices can be debugged. +EXIT CODE +--------- +evtest returns 1 on error. + +When used to query state, evtest returns 0 if the state bit is unset and +10 if the state bit is set. + SEE ALSO -------- inputattach(1) |