Linux proc file system

Directory and file Comment
/proc/N process PID is N
/proc/N/cmdline command start process
/proc/N/cwd link to process current word directory
/proc/N/environ Env var list for process
/proc/N/exe link to process executable command file
/proc/N/fd includes all file desc of process related file
/proc/N/maps process related memory info
/proc/N/mem memory space of current process, not readable
/proc/N/root root directory of process
/proc/N/stat status of process
/proc/N/statm memory status of process
/proc/N/status process status, better than stat and statm
/proc/self/ current process