Functions & Services of an OS

5. Handling i/o requests: As we discussed in the previous topic, an operating system handles i/o requests. That is, when an i/o device needs to transfer data (to or from the computer,) the operating system needs to take an appropriate action for the transfer to take place, such as by executing a particular i/o device driver. We will learn more about i/o in the next topic, "I/O and Interrupts".
6. Manipulating the file system: Files are stored on disk, but are associated with folders (a.k.a., directories). The operating system's role is to maintain the linkage between a file and its directory, between directories and their parent directories, and between the names of files and their corresponding storage locations on disk. More on this in the "File Management" topic of the course.
7. Process Communication: In many cases, two programs need to exchange data, such as when one calls the other. Various process communication techniques that programs use are managed by the operating system, such as signaling, pipes, and memory sharing. This topic will be covered in more detail in the "Processes" topic.