This recipe will show you how to check a number of figures related to the storage system. We will retrieve the filesystem's block size, the total number of blocks, and the number of free blocks. We can then use these figures to calculate a number of useful figures, such as the total disk capacity and how much space is used and free on the disk.
We'll then package all this code into a function to make it easier to call whenever we need access to this information. You can use the techniques shown in this recipe to achieve a number of things in your projects. For example, you could use it to find out how much total storage is available on the device since this varies between different boards. You can even use it to decide if the disk is getting too full and whether your script should delete some old log files.