1. Understanding ECF will help you understand important system concepts.
ECF是操作系统用来实现I/O,进程和虚拟内存的基本机制。
2. Understanding ECF will help you understand how applications interact with the operating system.
Applications use a form of ECF called traps or system calls to request services from the operating system. For example, writing data to the disk, reading data from the network, creating a new process, and terminating the current process are all achieved through application system calls. Understanding the basic system call mechanism will help you understand how these services are provided to the application.
3. Understanding ECF will help you write interesting new applications.
The operating system provides a powerful ECF mechanism for applications to create new processes, wait for process termination, notify other processes of abnormal events in the system, and detect and respond to these events. If you understand these ECF mechanisms, then you can use them to write interesting programs such as Unix shells and Web servers.
4. Understanding ECF will help you understand concurrency.
ECF is the basic mechanism for achieving concurrency in computer systems. Examples of concurrency in operation are: exception handlers that interrupt the execution of applications, progress and threads that overlap execution in time, and signal handlers that interrupt the execution of applications.
5. Understanding ECF will help you understand how software exceptions work.
Languages like C ++ and Java provide software exception mechanisms through try, catch, and throw statements. Software exceptions allow programs to perform non-local jumps (ie jumps that violate the usual call / return stack rules) in response to error conditions. Non-local jump is an application layer ECF, which is provided in C through setjmp and longjmp functions. Understanding these low-level functions will help you understand how high-level software exceptions can be implemented.
