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LINPROCFS(4)		    Kernel Interfaces Manual		  LINPROCFS(4)

NAME
       linprocfs -- Linux process file system

SYNOPSIS
       linprocfs	       /compat/linux/proc      linprocfs       rw 0 0

DESCRIPTION
       The  Linux  process  file  system,  or  linprocfs, emulates a subset of
       Linux' process file system and is required for the  complete  operation
       of some Linux binaries.

       The linprocfs provides a	two-level view of process space.  At the high-
       est  level,  processes themselves are named, according to their process
       ids in decimal, with no leading zeros.  There is	also  a	 special  node
       called  self  which  always refers to the process making	the lookup re-
       quest.

       Each process node is a directory	containing several files:

       auxv	      The auxiliary vector passed to the program.

       cmdline	      The command line used to execute the process.

       cwd	      A	symbolic link pointing to the current  work  directory
		      of the process.

       environ	      The  list	 of  environment  variables  and values	of the
		      process.	Every variable and  pair  value	 is  separated
		      from the next by a NULL byte.

       exe	      A	reference to the vnode from which the process text was
		      read.   This  can	be used	to gain	access to the process'
		      symbol table, or to start	another	copy of	the process.

       limits	      The soft and hard	limits for the process along with  the
		      units used.

       maps	      Memory map of the	process.

       mem	      The  complete virtual memory image of the	process.  Only
		      those addresses which exist in the process  can  be  ac-
		      cessed.	Reads  and  writes  to	this  file  modify the
		      process.	Writes to the text segment remain  private  to
		      the process.

       mountinfo      Information about	mount points.

       mounts	      Similar to the above.

       oom_score_adj  Score adjustment for the Out Of Memory killer.

       root	      Symbolic link to the root	directory for this process.

       stat	      Process  statistics.   It	 includes  user, nice, system,
		      idle, iowait, irq, softirq, steal, guest and guest_nice.

       statm	      Process size  statistics.	  It  includes	total  program
		      size, resident set size, number of resident shared pages
		      (unused),	text size, library size	(unused), data + stack
		      and dirty	pages (unused).

       status	      Process  statistics in human readable form.  It includes
		      process name, state, PID,	etc.

       task	      Dummy directory to avoid problems	in  specific  software
		      such as Chromium.

       Each  node  is  owned by	the process's user, and	belongs	to that	user's
       primary group, except for the mem  node,	 which	belongs	 to  the  kmem
       group.

FILES
       /compat/linux/proc	       The normal mount	point for linprocfs.
       /compat/linux/proc/cmdline      Contains	 the  path of the kernel image
				       used to boot the	system.
       /compat/linux/proc/cpuinfo      CPU vendor and model information	in hu-
				       man-readable form.
       /compat/linux/proc/devices      List of character  and  block  devices.
				       The later is usually empty on FreeBSD.
       /compat/linux/proc/filesystems  List  of	 supported  filesystems.   For
				       pseudo filesystems,  the	 first	column
				       contains	nodev.
       /compat/linux/proc/meminfo      System  memory  information  in	human-
				       readable	form.
       /compat/linux/proc/modules      Loaded kernel modules.  Empty for now.
       /compat/linux/proc/mounts       Devices corresponding mount points.
       /compat/linux/proc/mtab	       Same as above.
       /compat/linux/proc/partitions   Partition information  including	 major
				       and minor numbers, number of blocks and
				       name.   The  rest of the	fields are set
				       to zero.
       /compat/linux/proc/stat	       System statistics.  For each cpu	it in-
				       cludes at most user  time,  nice	 time,
				       system time and idle time, iowait (time
				       waiting	for  I/O  to  complete), times
				       serving irqs and	softirq, steal,	 guest
				       and  guest_nice	times  that  represent
				       times spent in  different  modes	 in  a
				       virtualized   environment.    The  last
				       columns are set	to  zero.   This  file
				       also   contains	brief  statistics  for
				       disks, context switches and more.
       /compat/linux/proc/swap	       Information about the  swap  device  if
				       any.
       /compat/linux/proc/uptime       Time since the last boot	and time spent
				       in idle state.
       /compat/linux/proc/version      Version of the emulated linux system.
       /compat/linux/proc/pid	       A directory containing process informa-
				       tion for	process	pid.
       /compat/linux/proc/self	       A directory containing process informa-
				       tion for	the current process.

EXAMPLES
       To mount	a linprocfs file system	on /compat/linux/proc:

	     mount -t linprocfs	linprocfs /compat/linux/proc

SEE ALSO
       mount(2), unmount(2), auxv(3), linux(4),	procfs(5), pseudofs(9)

HISTORY
       The linprocfs first appeared in FreeBSD 4.0.

AUTHORS
       The  linprocfs  was derived from	procfs by Pierre Beyssac.  This	manual
       page was	written	by Dag-Erling Smorgrav,	based on the procfs(5)	manual
       page by Garrett Wollman.

FreeBSD	15.0			 May 29, 2025			  LINPROCFS(4)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=linprocfs&manpath=FreeBSD+15.0-RELEASE+and+Ports>

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