What options do we have for communication between a user program and a Linux Kernel Module?

Question

I am a new comer to Linux Kernel Module programming. From the material that I have read so far, I have found that there are 3 ways for a user program to request services or to communicate with a Linux Kernel Module

1. a device file in /dev
2. a file in /proc file system
3. ioctl() call

Question: What other options do we have for communication between user program and linux kernel module?

Answer 1

Your option 3) is really a sub-option of option 1) - ioctl() is one way of interacting with a device file (read() and write() being the usual ways).

Two other ways worth considering are:

• The sysfs filesystem;
• Netlink sockets.