# os

    Stability: 4 - API Frozen

Provides a few basic operating-system related utility functions.

Use `require('os')` to access this module.

## os.tmpdir()

Returns the operating system's default directory for temp files.

## os.endianness()

Returns the endianness of the CPU. Possible values are `"BE"` or `"LE"`.

## os.hostname()

Returns the hostname of the operating system.

## os.type()

Returns the operating system name.

## os.platform()

Returns the operating system platform.

## os.arch()

Returns the operating system CPU architecture.

## os.release()

Returns the operating system release.

## os.uptime()

Returns the system uptime in seconds.

## os.loadavg()

Returns an array containing the 1, 5, and 15 minute load averages.

The load average is a measure of system activity, calculated by the operating
system and expressed as a fractional number.  As a rule of thumb, the load
average should ideally be less than the number of logical CPUs in the system.

The load average is a very UNIX-y concept; there is no real equivalent on
Windows platforms.  That is why this function always returns `[0, 0, 0]` on
Windows.

## os.totalmem()

Returns the total amount of system memory in bytes.

## os.freemem()

Returns the amount of free system memory in bytes.

## os.cpus()

Returns an array of objects containing information about each CPU/core
installed: model, speed (in MHz), and times (an object containing the number of
milliseconds the CPU/core spent in: user, nice, sys, idle, and irq).

Example inspection of os.cpus:

    [ { model: 'Intel(R) Core(TM) i7 CPU         860  @ 2.80GHz',
        speed: 2926,
        times:
         { user: 252020,
           nice: 0,
           sys: 30340,
           idle: 1070356870,
           irq: 0 } },
      { model: 'Intel(R) Core(TM) i7 CPU         860  @ 2.80GHz',
        speed: 2926,
        times:
         { user: 306960,
           nice: 0,
           sys: 26980,
           idle: 1071569080,
           irq: 0 } },
      { model: 'Intel(R) Core(TM) i7 CPU         860  @ 2.80GHz',
        speed: 2926,
        times:
         { user: 248450,
           nice: 0,
           sys: 21750,
           idle: 1070919370,
           irq: 0 } },
      { model: 'Intel(R) Core(TM) i7 CPU         860  @ 2.80GHz',
        speed: 2926,
        times:
         { user: 256880,
           nice: 0,
           sys: 19430,
           idle: 1070905480,
           irq: 20 } },
      { model: 'Intel(R) Core(TM) i7 CPU         860  @ 2.80GHz',
        speed: 2926,
        times:
         { user: 511580,
           nice: 20,
           sys: 40900,
           idle: 1070842510,
           irq: 0 } },
      { model: 'Intel(R) Core(TM) i7 CPU         860  @ 2.80GHz',
        speed: 2926,
        times:
         { user: 291660,
           nice: 0,
           sys: 34360,
           idle: 1070888000,
           irq: 10 } },
      { model: 'Intel(R) Core(TM) i7 CPU         860  @ 2.80GHz',
        speed: 2926,
        times:
         { user: 308260,
           nice: 0,
           sys: 55410,
           idle: 1071129970,
           irq: 880 } },
      { model: 'Intel(R) Core(TM) i7 CPU         860  @ 2.80GHz',
        speed: 2926,
        times:
         { user: 266450,
           nice: 1480,
           sys: 34920,
           idle: 1072572010,
           irq: 30 } } ]

## os.networkInterfaces()

Get a list of network interfaces:

    { lo0: 
       [ { address: '::1', family: 'IPv6', internal: true },
         { address: 'fe80::1', family: 'IPv6', internal: true },
         { address: '127.0.0.1', family: 'IPv4', internal: true } ],
      en1: 
       [ { address: 'fe80::cabc:c8ff:feef:f996', family: 'IPv6',
           internal: false },
         { address: '10.0.1.123', family: 'IPv4', internal: false } ],
      vmnet1: [ { address: '10.99.99.254', family: 'IPv4', internal: false } ],
      vmnet8: [ { address: '10.88.88.1', family: 'IPv4', internal: false } ],
      ppp0: [ { address: '10.2.0.231', family: 'IPv4', internal: false } ] }

## os.EOL

A constant defining the appropriate End-of-line marker for the operating system.