Notes on /proc and /sys - Revision history

Scellef: /* System Information */ Typo

2012-12-28T23:51:58Z

System Information: Typo

Scellef: /* System Information */ added kmsg and version

2012-12-28T23:51:30Z

System Information: added kmsg and version

Scellef at 21:39, 5 February 2012

2012-02-05T21:39:30Z

Scellef: Created page with "Under the [http://www.pathname.com/fhs/ Filesystem Heirarchy Standard], `/proc` is a directories that mounts a [http://en.wikipedia.org/wiki/Procfs procfs] filesystem.…"

2012-02-05T21:31:11Z

Created page with "Under the [http://www.pathname.com/fhs/ Filesystem Heirarchy Standard], <code>/proc</code> is a directories that mounts a [http://en.wikipedia.org/wiki/Procfs procfs] filesystem.…"

New page

Under the [http://www.pathname.com/fhs/ Filesystem Heirarchy Standard], <code>/proc</code> is a directories that mounts a [http://en.wikipedia.org/wiki/Procfs procfs] filesystem. In newer kernels, the functions of <code>/proc</code> are being superseded by <code>/sys</code>, which uses the [http://en.wikipedia.org/wiki/Sysfs sysfs] filesystem. These filesystems are designed to offer information about current processes, drivers, and devices running on the operating system and enable some configuration of the host operating system.

==Getting information from <code>/proc</code>==
The following are some files under <code>/proc</code> I find to occasionally be useful.
===Hardware Information===
;<code>/proc/cpuinfo</code>
:A detailed listing of the processor(s) model, speed, cache sizes, flags, and more. Corresponds to <code>lscpu</code>
;<code>/proc/meminfo</code>
:A verbose report on the system's memory. Corresponds to <code>free</code>
;<code>/proc/acpi/battery/</code>
:Directories named after batteries known to the system, with files detailing information and their current state. Corresponds to <code>acpi</code>
;<code>/proc/mdstat</code>
:A listing of the RAID devices known to the system and their current state. Corresponds to <code>mdadm --detail --scan</code>
;<code>/proc/scsi/scsi</code>
:A listing of all disk drives, their type, and which bus they reside on (including optical drives, or drives connected through external interfaces such as USB)

===System Information===
;<code>/proc/loadavg</code>
:Load average numbers on the system. Corresponds to <code>uptime</code>
;<code>/proc/uptime</code>
:Time since the system was booted. Corresponds to <code>uptime</code>, and the kernel parameter <code>printk.time</code>
;<code>/proc/mounts</code>
:A listing of currently mounted devices and filesystems. Corresponds to <code>mount</code>
;<code>/proc/partitions</code>
:A listing of the devices, their partitions and number of blocks used known to the operating system
;<code>/proc/swaps</code>
:A listing of all swap partitions available to the system
;<code>/proc/kcore</code>
:A dump of the system's current memory. There is much <del>evil</del> fun to be had here.
;<code>/prov/self/environ</code>
:A listing of all environmental variables. Corresponds to <code>env</code>
;<code>/proc/modules</code>
:A list of all modules currently loaded in the kernel. Corresponds to <code>lsmod</code>

===System Configuration===
;<code>/proc/sys/kernel/domainname</code>
:Prints the system's domain name, if any. Corresponds to <code>domainname</code>, and <code>dnsdomainname</code>
;<code>/proc/sys/kernel/hostname</code>
:Prints the system's host name, if any. Corresponds to <code>hostname</code>, and <code>dnsdomainname</code>
;<code>/proc/sys/kernel/ctrl+alt+del</code>
:Returns either a <code>0</code> or a <code>1</code>
::<code>0</code> indicates that the key sequence will be captured by init and initiate a graceful shutdown
::<code>1</code> indicates that the key sequence will not be captured, and will shutdown as though you had yanked the power plug
;<code>/proc/sys/kernel/sysrq</code>
:A non-zero integer indicates that [http://en.wikipedia.org/wiki/Magic_SysRq_key SysRq] key sequences will be acknowledged.

@@ Line 35: / Line 35: @@
 :A dump of messages from the kernel.  Corresponds to <code>dmesg</code> (NOTE: This will empty the buffer of kernel messages)
 ;<code>/proc/version</code>
-:Displays the kernel version, revision, architecture, compiler, etc.  Corresponds to </code>uname</code>.
+:Displays the kernel version, revision, architecture, compiler, etc.  Corresponds to <code>uname</code>.
 ===System Configuration===

← Older revision		Revision as of 21:39, 5 February 2012
Line 1:		Line 1:
−	Under the [http://www.pathname.com/fhs/ Filesystem Heirarchy Standard], <code>/proc</code> is a ~~directories~~ that mounts a [http://en.wikipedia.org/wiki/Procfs procfs] filesystem. In newer kernels, the functions of <code>/proc</code> are being superseded by <code>/sys</code>, which uses the [http://en.wikipedia.org/wiki/Sysfs sysfs] filesystem. These filesystems are designed to offer information about current processes, drivers, and devices running on the operating system and enable some configuration of the host operating system.	+	Under the [http://www.pathname.com/fhs/ Filesystem Heirarchy Standard], <code>/proc</code> is a directory that mounts a [http://en.wikipedia.org/wiki/Procfs procfs] filesystem. In newer kernels, the functions of <code>/proc</code> are being superseded by <code>/sys</code>, which uses the [http://en.wikipedia.org/wiki/Sysfs sysfs] filesystem. These filesystems are designed to offer information about current processes, drivers, and devices running on the operating system and enable some configuration of the host operating system.

	==Getting information from <code>/proc</code>==		==Getting information from <code>/proc</code>==

@@ Line 17: / Line 17: @@
 ===System Information===
 ;<code>/proc/loadavg</code>
-:Load average numbers on the system.  Corresponds to <code>uptime</code>
+:Load average numbers on the system.  Corresponds to <code>uptime</code>.
 ;<code>/proc/uptime</code>
-:Time since the system was booted.  Corresponds to <code>uptime</code>, and the kernel parameter <code>printk.time</code>
+:Time since the system was booted.  Corresponds to <code>uptime</code>, and the kernel parameter <code>printk.time</code>.
 ;<code>/proc/mounts</code>
-:A listing of currently mounted devices and filesystems.  Corresponds to <code>mount</code>
+:A listing of currently mounted devices and filesystems.  Corresponds to <code>mount</code>.
 ;<code>/proc/partitions</code>
-:A listing of the devices, their partitions and number of blocks used known to the operating system
+:A listing of the devices, their partitions and number of blocks used known to the operating system.
 ;<code>/proc/swaps</code>
-:A listing of all swap partitions available to the system
+:A listing of all swap partitions available to the system.
 ;<code>/proc/kcore</code>
 :A dump of the system's current memory.  There is much <del>evil</del> fun to be had here.
 ;<code>/prov/self/environ</code>
-:A listing of all environmental variables.  Corresponds to <code>env</code>
+:A listing of all environmental variables.  Corresponds to <code>env</code>.
 ;<code>/proc/modules</code>
-:A list of all modules currently loaded in the kernel.  Corresponds to <code>lsmod</code>
+:A list of all modules currently loaded in the kernel.  Corresponds to <code>lsmod</code>.
 ===System Configuration===

Notes on /proc and /sys - Revision history

Scellef: /* System Information */ Typo

Scellef: /* System Information */ added kmsg and version

Scellef at 21:39, 5 February 2012

Scellef: Created page with "Under the [http://www.pathname.com/fhs/ Filesystem Heirarchy Standard], /proc is a directories that mounts a [http://en.wikipedia.org/wiki/Procfs procfs] filesystem.…"

Scellef: Created page with "Under the [http://www.pathname.com/fhs/ Filesystem Heirarchy Standard], `/proc` is a directories that mounts a [http://en.wikipedia.org/wiki/Procfs procfs] filesystem.…"