Simple command to monitor directory changes on Mac

Sometimes you want to know if a certain App/code/IDE changed something on the disk, this little script / command may come in handy.

Install fswatch

install fswatch as a global command

The script

Only fswatch is not enough, here is the script that does the trick

Save as a script e.g., then give it executable permission

Now run the script and supply the path as parameter, and you will start monitoring the directory


Migrating to “Docker for Mac” from Toolbox

As Docker for Mac becomes available, it’s about time to ditch Docker Toolbox which requires a VM running in background. The migration is surprisingly easy. The Official doc recommend you to read this article “Docker for Mac vs. Docker Toolbox“, while I think it’s a pretty good read, I will simply tell you the steps to migrate if you just need the info. Continue reading

Using SoundPool in Android

If your app/game need to play a sound when user click certain object, you will quickly found out that using MediaPlayer is a bad idea. This is what SoundPool is for, however, its API is still a bit unfriendly. This is some notes on how to use it and my suggested usage pattern.

Obtaining a SoundPool object

It is recommended to use the Builder, but lower SDK device does not support that, so this Continue reading

Docker commands to clean unused images

If you use docker for some time, there will be a lot of trash images, volumes that is not used by any containers. Here’s how to remove them. (warning: not reversible)

Remove dangling images

Remove dangling volumes

As seen from above commands, you may guess the nested command within the $(…) is used to list dangling images/volumes

List dangling images

List dangling volumes

Docker named volume explained

Named volume is a new feature since Docker 1.9, it allows you to manage persistent data more easily, and also the volume can be provided by other storage drivers such as Glusterfs instead of “just a directory on the host”. This new feature is particularly useful in production environment. (On the Dev side, I think we still need mounted volume) Continue reading

PHP Traits – why is it useful

I know I’m late into the game but I recently found that Traits in PHP is really useful. PHP Traits come in handy if you have some part of a class you wish to re-use in the future in another class, but you don’t want strict inheritance relationship.

What is Traits

PHP Trait defines a code segment that is simply copy-n-pasted into a class at compile time. It can contains variables, constants, methods, Continue reading