How can we create 'special' files, like /dev/random, in linux?

Question

In Linux file system, there are files such as /dev/zero and /dev/random which are not real files on hard disk.

Is there any way that we can create a similar file and tell it to get ouput from executing a program?

For example, can I create file, say /tmp/tarfile, such that any program reading it actually gets the output from the execution of a different program (/usr/bin/tar ...)?

Answer 1

可以创建这样的文件/程序，但是需要创建一个特殊的文件系统才能将钩子插入VFS，以便可以检测和正确处理访问。