Where we can find log file of KEXTs in Mac OS?

Question

I have created a sample kext used the below code to write a log.

IOLog("scan\n");

I have loaded kext by running below command in terminal.

sudo kextload mykext.kext

it loaded sucessfully when i check system.log file unable to find logs written in code.

Answer 1

You wont be able to find the log file, because there is no such. You should use log utility in terminal: sudo log show

The output of this command is huge.

There are some built-in options that could help you to filter, like --last 5m, but I recomend to write all your driver messages with some stable prefix, like "MyDriver:", so you can use the log with | grep MyDriver: