Wait For Device

Introduction

w4d is a small command line program which waits for a device to be available and then exits

The idea is that you run this in your for example rc.local script before you start a program like Motion which will fail if the USB camera is not yet found by the system.

Detailed Description

The w4d (wait for device) tool simply waits for a device to become available and then exits.

In Linux when you modprobe the usb-devices everything will be scanned in an async manor, so you need to fiddle around with sleeps and such before you call a program like Motion.

w4d prevents this. It will check for a device to become available and then exit. After that you can let your startupscripts start motion for example.

Attached Files

The project is hosted at the authors website

http://www.vanheusden.com/w4d/

Installation

make make install

Users Guide

Enter: w4d -h

to see a list of options.

Example usage:

w4d -d /dev/video0 -i 250 -n 10

check 4 times a second for 2.5 seconds if device /dev/video0 comes available.

Comments and Bug Reports

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