222: Filesystem: Why Should You Learn To Use It?
Take Up Code - Podcast autorstwa Take Up Code: build your own computer games, apps, and robotics with podcasts and live classes
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Understanding how to use the filesystem will allow you to add common and expected features to your apps. Listen to the full episode for more insight into filesystems. And make sure to subscribe to the podcast from within your podcast app to get new episodes automatically. You can also read the full transcript below. Transcript How many times have you needed to save your work? Maybe you’re writing a document and need to save it so that you can continue working on it later. I don’t know anybody that can write more than a few pages perfectly the first time and then have no need of that document after printing it. Even emailing your work requires it to be saved somewhere. And documents aren’t the only thing that needs to be saved. Maybe you’re playing a game and want to save your progress so you can continue playing later. Now you could just leave everything as is in memory. Just pause the game or leave the document open. Then come back to it whenever you want. That works until you lose power. Or until some bug causes the application to crash. And then there’s the question of size. Modern games are much too big to fit everything into memory at once. Maybe a word processor can fit everything into memory including a full novel that you’re writing. But that’s because even the longest novel is insignificant in size compared to all the data needed by an immersive game world. What about pictures and video? It wouldn’t be very good if you couldn’t do anything with a picture except look at it right after it was taken. We need to save things to a permanent storage location that we can rely on to exist after turning off a device or a computer. This has been possible for so many years that it’s just expected. Nobody really considers it optional anymore. It would be like buying a car with an optional air conditioner. A long time ago, cars didn’t have air conditioners. Or power steering. Or power windows that can be opened and closed with the press of a button. To this day, people still say to roll down the window. There was a time when computers came with optional disk drives. Some early computers didn’t even have this as an option. You would turn on the computer, do whatever you wanted, and lose everything when you turned it off. Some computers were designed to use a tape recorder to save your work. The same kind of tape recorder that people used to record and play voices and music. When I was a kid, I would wait patiently next to the stereo for a song to play that I liked and sit as quiet as possible while holding the tape recorder next to the speaker to record the song. The recording quality was terrible even when I could avoid dogs barking or birds chirping. The computers would emit a series of tones or beeping sounds whenever you wanted to save your work. The only good thing was that the recording was done through a cable instead of telling everybody to be quiet so you could save your work. It was still a long process with quite a few steps. And it was slow. I’m skipping over even earlier computers that used paper cards or rolls of paper tape to store information. They could punch holes in the paper and then read information back by looking for the holes. I just don’t have any direct experience with these computers. Early main frame computers did have the ability to store information on magnetic disks or magnetic tape. Some disks were removable and some were fixed. The tape was stored in large cartridges that could be loaded into even larger tape players. Some removable disks were larger than birthday cakes and were the type of thing that you might ask for help carrying. The removable disks became smaller and flexible and could fit inside a binder with regular papers. They were about 8 inches in diameter and kept inside a protective sleeve so that people could hold them without getting fingerprints on the actual magnetic surface. These types of disks bec