/proc filesystem
Posted on :: Updated on :: storage

It's a virtual filesystem which provides interface to kernel internal data structures, which looks like traditional files and dirs. It's created on the fly by the kernel as process access them.

Important files

/proc

  • /proc/version - kernel version
  • /proc/self - a process can access it's own proc pid dir at /proc/self
  • /proc/net - status info about networking & sockets
  • /proc/sys/fs - settings related to filesystems
  • /proc/sys/kernel - kernel settings
  • /proc/sys/net - networking settings
  • /proc/sys/vm - memory management settings

/proc/PID

  • /proc/PID/status - contains runtime info about the process
  • /proc/PID/cmdline - command line arguments used to invoke
  • /proc/PID/cwd - current working dir of the process
  • /proc/PID/environ - environment variables
  • /proc/PID/exe - symlink to executable binary
  • /proc/PID/fd - symlink to files opened
  • /proc/PID/maps - memory mapping
  • /proc/PID/mem - process virtual memory
  • /proc/PID/mounts - mountpoints for this process
  • /proc/PID/root - symlink to the root dir
  • /proc/PID/task - one subdir per thread

Sources