=======
GPIOMON
=======

:Date: June 2026

NAME
====

gpiomon - libgpiod command-line utility

SYNOPSIS
========

**gpiomon** [*OPTIONS*] *<line>*...

DESCRIPTION
===========

Wait for events on GPIO lines and print them to standard output.

Lines are specified by name, or optionally by offset if the chip option is provided.

OPTIONS
=======

**--banner**
   display a banner on successful startup

**-b**, **--bias** <bias>
   specify the line bias Possible values: 'pull-down', 'pull-up', 'disabled'. (default is to leave bias unchanged)

**--by-name**
   treat lines as names even if they would parse as an offset

**-c**, **--chip** <chip>
   restrict scope to a particular chip

**-C**, **--consumer** <name> consumer name applied to requested lines (default is 'gpiomon')

**-e**, **--edges** <edges>
   specify the edges to monitor Possible values: 'falling', 'rising', 'both'. (default is 'both')

**-E**, **--event-clock** <clock>
   specify the source clock for event timestamps Possible values: 'monotonic', 'realtime', 'hte'. (default is 'monotonic') By default 'realtime' is formatted as UTC, others as raw u64.

**-h**, **--help**
   display this help and exit

**-F**, **--format** <fmt>
   specify a custom output format

**--idle-timeout** <period>
   exit gracefully if no events occur for the period specified

**-l**, **--active-low**
   treat the line as active low, flipping the sense of rising and falling edges

**--localtime**
   format event timestamps as local time

**-n**, **--num-events** <num>
   exit after processing num events

**-p**, **--debounce-period** <period>
   debounce the line(s) with the specified period

**-q**, **--quiet**
   don't generate any output

**-I**, **--initial-state**
   print initial states of the lines

**-N**, **--numeric**
   display line values as '0' (inactive) or '1' (active)

**-s**, **--strict**
   abort if requested line names are not unique

**--unquoted**
   don't quote line or consumer names

**--utc**
   format event timestamps as UTC (default for 'realtime')

**-v**, **--version**
   output version information and exit

Chips:
------

   A GPIO chip may be identified by number, name, or path. e.g. '0', 'gpiochip0', and '/dev/gpiochip0' all refer to the same chip.

Periods:
--------

   Periods are taken as milliseconds unless units are specified. e.g. 10us. Supported units are 'm', 's', 'ms', and 'us' for minutes, seconds, milliseconds and microseconds respectively.

Format specifiers:
------------------

%o
   GPIO line offset

%l
   GPIO line name

%c
   GPIO chip name

%e
   numeric edge event type ('1' - rising or '2' - falling)

%E
   edge event type ('rising' or 'falling')

%S
   event timestamp as seconds

%U
   event timestamp as UTC

%L
   event timestamp as local time

AUTHOR
======

Bartosz Golaszewski <brgl@kernel.org>

REPORTING BUGS
==============

Report bugs to: Bartosz Golaszewski <brgl@kernel.org> linux-gpio <linux-gpio@vger.kernel.org>

COPYRIGHT
=========

| Copyright © 2017-2023 Bartosz Golaszewski License: GPL-2.0-or-later
| This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.