EVIOTEST

NAME

eviotest — test the setup of an input device connected via the Linux input event systems (aka evdev or EVIO).  

SYNOPSIS

eviotest [-list] [-nodata] [-repunk] [<event device>]  

DESCRIPTION

The eviotest program is used to interface with devices connected via the Linux input event system. This system is sometimes called "evdev", or can be referenced by the IOCTL code of "EVIO". The eviotest program can be used to list input devices and provide their self-reported names, or to provide a live report of the inputs.

Before rendering the input stream, eviotest will output information specific to the input device such as the number and name of all button inputs, absolute axis (aka valuator) inputs and all relative axis inputs. NOTE: many event inputs have restrictive permissions and can only be accessed with escalated permissions (ie. sudo).

The program is terminated by pressing the interrupt key (usually ^C). Note that sometimes this doesn't fully work the first time, but it will work the second time.  

OPTIONS

-list

The -list option lists all Linux event devices of the form "/dev/input/event<N>", where N is from [0:512]. It will only list devices that exist. For devices that exist, but for which the current user does not have permission to access, then this information will be reported. All other arguments are ignored when "-list" is specified. NOTE again: many event inputs have restrictive permissions and will not even be listable without the use of escalated permissions (ie. sudo).

-nodata

The -nodata option reports detailed information about the device and then exits. The reported data includes the name of the device, the manufacturer id, and item code as well as the name and number of all inputs.

-repunk

The -repunk option will report all unknown input events. Typically, unknown events will go unreported so as to not sully the event output with undesired information. However, for debugging purposes it may be of interest to know whether there are other input events being received, and what they might be.

ARGUMENTS

[<event device>]

The <event device> argument is a filesystem path pointing to a specific Linux input event device — for example "/dev/input/event5".

ENVIRONMENT VARIABLES

EVIO_DEVICE

Set the path of the default input device to read when no device argument is provided.

EXAMPLES

List all Linux input event devices:

% eviotest -list

Report inputs from the device at "/dev/input/event5":

% eviotest /dev/input/event5

Set the default input device to be "/dev/input/event6" and then report those events:

% setenv EVIO_DEVICE /dev/input/event6
% eviotest

BUGS

The fact that eviotest does not always terminate when receiving the first interrupt signal (ie. ^C) may be considered a bug. The workaround is already coded in the program — just send a second interrupt.  

TODO

•

It would be nice to manipulate device LEDs

•

It would be nice to manipulate device force feedback events

•

Implement a screen-rendering option

SEE ALSO

joytest(1fv), vrpntest(1fv), vruiddtest(1fv), dtracktest(1fv), fobtest(1fv), freevr(7fv), evtest(1), evdev(4)  

LOCATION

The source code for eviotest is in the "vr_input.evio.c" file, which also handles the EVIO input interface to the FreeVR library.  

COPYRIGHT

Copyright 2024, Bill Sherman, All rights reserved.

Index

NAME

SYNOPSIS

DESCRIPTION

OPTIONS

ARGUMENTS

ENVIRONMENT VARIABLES

EXAMPLES

BUGS

TODO

SEE ALSO

LOCATION

COPYRIGHT