The /proc File System

来源：http://www.faqs.org/docs/kernel/x716.html

In Linux there is an additional mechanism for the kernel and kernel modules to send information to processes --- the/proc file system. Originally designed to allow easy access to information aboutprocesses (hence the name), it is now used by every bit of the kernel which has something interesting to report, such as/proc/modules which has the list of modules and/proc/meminfo which has memory usagestatistics.

The method to use the proc file system is very similar to the one used with device drivers --- you create a structurewith all the information needed for the/proc file, including pointers to any handlerfunctions (in our case there is only one, the one called when somebody attempts to read from the/proc file). Then, init_module registers the structure with the kernel andcleanup_module unregisters it.

/proc 文件系统本来是被用来存放进程信息的，后来发展成为内核中只要需要report的的部分都放在了这个文件系统中。