node/doc/api/os.md

# OS

    Stability: 2 - Stable

Provides a few basic operating-system related utility functions.

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

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

## os.arch()
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Returns the operating system CPU architecture. Possible values are `'x64'`,
`'arm'` and `'ia32'`. Returns the value of [`process.arch`][].

## os.constants

Returns an object containing commonly used operating system specific constants
for error codes, process signals, and so on. The specific constants currently
defined are described in [OS Constants][].

## os.cpus()
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added: v0.3.3
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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:

```js
[ { 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 } } ]
```

Note that since `nice` values are UNIX centric in Windows the `nice` values of
all processors are always 0.

## os.endianness()
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Returns the endianness of the CPU. Possible values are `'BE'` for big endian
or `'LE'` for little endian.

## os.freemem()
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Returns the amount of free system memory in bytes.

## os.homedir()
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Returns the home directory of the current user.

## os.hostname()
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Returns the hostname of the operating system.

## os.loadavg()
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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.networkInterfaces()
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added: v0.6.0
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Get a list of network interfaces:

```js
{ lo:
   [ { address: '127.0.0.1',
       netmask: '255.0.0.0',
       family: 'IPv4',
       mac: '00:00:00:00:00:00',
       internal: true },
     { address: '::1',
       netmask: 'ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff',
       family: 'IPv6',
       mac: '00:00:00:00:00:00',
       internal: true } ],
  eth0:
   [ { address: '192.168.1.108',
       netmask: '255.255.255.0',
       family: 'IPv4',
       mac: '01:02:03:0a:0b:0c',
       internal: false },
     { address: 'fe80::a00:27ff:fe4e:66a1',
       netmask: 'ffff:ffff:ffff:ffff::',
       family: 'IPv6',
       mac: '01:02:03:0a:0b:0c',
       internal: false } ] }
```

Note that due to the underlying implementation this will only return network
interfaces that have been assigned an address.

## os.platform()
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added: v0.5.0
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Returns the operating system platform. Possible values are `'darwin'`,
`'freebsd'`, `'linux'`, `'sunos'` or `'win32'`. Returns the value of
[`process.platform`][].

## os.release()
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Returns the operating system release.

## os.tmpdir()
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Returns the operating system's default directory for temporary files.

## os.totalmem()
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Returns the total amount of system memory in bytes.

## os.type()
<!-- YAML
added: v0.3.3
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Returns the operating system name. For example `'Linux'` on Linux, `'Darwin'`
on OS X and `'Windows_NT'` on Windows.

## os.uptime()
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Returns the system uptime in seconds.

## os.userInfo([options])
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* `options` {Object}
  * `encoding` {String} Character encoding used to interpret resulting strings.
    If `encoding` is set to `'buffer'`, the `username`, `shell`, and `homedir`
    values will be `Buffer` instances. (Default: 'utf8')

Returns a subset of the password file entry for the current effective user. The
returned object includes the `username`, `uid`, `gid`, `shell`, and `homedir`.
On Windows, the `uid` and `gid` fields are `-1`, and `shell` is `null`.

The value of `homedir` returned by `userInfo()` comes directly from the
operating system. This differs from the result of `os.homedir()`, which queries
several environment variables for the home directory before falling back to the
operating system response.

## OS Constants

The following constants are exported by `os.constants`. **Note:** Not all
constants will be available on every operating system.

### Signal Constants

The following signal constants are exported by `os.constants.signals`:

<table>
  <tr>
    <th>Constant</th>
    <th>Description</th>
  </tr>
  <tr>
    <td><code>SIGHUP</code></td>
    <td>Sent to indicate when a controlling terminal is closed or a parent
    process exits.</td>
  </tr>
  <tr>
    <td><code>SIGINT</code></td>
    <td>Sent to indicate when a user wishes to interrupt a process 
    (`(Ctrl+C)`).</td>
  </tr>
  <tr>
    <td><code>SIGQUIT</code></td>
    <td>Sent to indicate when a user wishes to terminate a process and perform a
    core dump.</td>
  </tr>
  <tr>
    <td><code>SIGILL</code></td>
    <td>Sent to a process to notify that it has attempted to perform an illegal,
    malformed, unknown or privileged instruction.</td>
  </tr>
  <tr>
    <td><code>SIGTRAP</code></td>
    <td>Sent to a proces when an exception has occurred.</td>
  </tr>
  <tr>
    <td><code>SIGABRT</code></td>
    <td>Sent to a process to request that it abort.</td>
  </tr>
  <tr>
    <td><code>SIGIOT</code></td>
    <td>Synonym for <code>SIGABRT</code></td>
  </tr>
  <tr>
    <td><code>SIGBUS</code></td>
    <td>Sent to a process to notify that it has caused a bus error.</td>
  </tr>
  <tr>
    <td><code>SIGFPE</code></td>
    <td>Sent to a process to notify that it has performed an illegal arithmetic 
    operation.</td>
  </tr>
  <tr>
    <td><code>SIGKILL</code></td>
    <td>Sent to a process to terminate it immediately.</td>
  </tr>
  <tr>
    <td><code>SIGUSR1</code> <code>SIGUSR2</code></td>
    <td>Sent to a process to identify user-defined conditions.</td>
  </tr>
  <tr>
    <td><code>SIGSEGV</code></td>
    <td>Sent to a process to notify of a segmentation fault.</td>
  </tr>
  <tr>
    <td><code>SIGPIPE</code></td>
    <td>Sent to a process when it has attempted to write to a disconnected
    pipe.</td>
  </tr>
  <tr>
    <td><code>SIGALRM</code></td>
    <td>Sent to a process when a system timer elapses.</td>
  </tr>
  <tr>
    <td><code>SIGTERM</code></td>
    <td>Sent to a process to request termination.</td>
  </tr>
  <tr>
    <td><code>SIGCHLD</code></td>
    <td>Sent to a process when a child process terminates.</td>
  </tr>
  <tr>
    <td><code>SIGSTKFLT</code></td>
    <td>Sent to a process to indicate a stack fault on a coprocessor.</td>
  </tr>
  <tr>
    <td><code>SIGCONT</code></td>
    <td>Sent to instruct the operating system to continue a paused process.</td>
  </tr>
  <tr>
    <td><code>SIGSTOP</code></td>
    <td>Sent to instruct the operating system to halt a process.</td>
  </tr>
  <tr>
    <td><code>SIGTSTP</code></td>
    <td>Sent to a process to request it to stop.</td>
  </tr>
  <tr>
    <td><code>SIGBREAK</code></td>
    <td>Sent to indicate when a user wishes to interrupt a process.</td>
  </tr>
  <tr>
    <td><code>SIGTTIN</code></td>
    <td>Sent to a process when it reads from the TTY while in the
    background.</td>
  </tr>
  <tr>
    <td><code>SIGTTOU</code></td>
    <td>Sent to a process when it writes to the TTY while in the
    background.</td>
  </tr>
  <tr>
    <td><code>SIGURG</code></td>
    <td>Sent to a process when a socket has urgent data to read.</td>
  </tr>
  <tr>
    <td><code>SIGXCPU</code></td>
    <td>Sent to a process when it has exceeded its limit on CPU usage.</td>
  </tr>
  <tr>
    <td><code>SIGXFSZ</code></td>
    <td>Sent to a process when it grows a file larger than the maximum
    allowed.</td>
  </tr>
  <tr>
    <td><code>SIGVTALRM</code></td>
    <td>Sent to a process when a virtual timer has elapsed.</td>
  </tr>
  <tr>
    <td><code>SIGPROF</code></td>
    <td>Sent to a process when a system timer has elapsed.</td>
  </tr>
  <tr>
    <td><code>SIGWINCH</code></td>
    <td>Sent to a process when the controlling terminal has changed its
    size.</td>
  </tr>
  <tr>
    <td><code>SIGIO</code></td>
    <td>Sent to a process when I/O is available.</td>
  </tr>
  <tr>
    <td><code>SIGPOLL</code></td>
    <td>Synonym for <code>SIGIO</code></td>
  </tr>
  <tr>
    <td><code>SIGLOST</code></td>
    <td>Sent to a process when a file lock has been lost.</td>
  </tr>
  <tr>
    <td><code>SIGPWR</code></td>
    <td>Sent to a process to notify of a power failure.</td>
  </tr>
  <tr>
    <td><code>SIGINFO</code></td>
    <td>Synonym for <code>SIGPWR</code></td>
  </tr>
  <tr>
    <td><code>SIGSYS</code></td>
    <td>Sent to a process to notify of a bad argument.</td>
  </tr>
  <tr>
    <td><code>SIGUNUSED</code></td>
    <td>Synonym for <code>SIGSYS</code></td>
  </tr>
</table>

### Error Constants

The following error constants are exported by `os.constants.errno`:

#### POSIX Error Constants

<table>
  <tr>
    <th>Constant</th>
    <th>Description</th>
  </tr>
  <tr>
    <td><code>E2BIG</code></td>
    <td>Indicates that the list of arguments is longer than expected.</td>
  </tr>
  <tr>
    <td><code>EACCES</code></td>
    <td>Indicates that the operation did not have sufficient permissions.</td>
  </tr>
  <tr>
    <td><code>EADDRINUSE</code></td>
    <td>Indicates that the network address is already in use.</td>
  </tr>
  <tr>
    <td><code>EADDRNOTAVAIL</code></td>
    <td>Indicates that the network address is currently unavailable for
    use.</td>
  </tr>
  <tr>
    <td><code>EAFNOSUPPORT</code></td>
    <td>Indicates that the network address family is not supported.</td>
  </tr>
  <tr>
    <td><code>EAGAIN</code></td>
    <td>Indicates that there is currently no data available and to try the
    operation again later.</td>
  </tr>
  <tr>
    <td><code>EALREADY</code></td>
    <td>Indicates that the socket already has a pending connection in
    progress.</td>
  </tr>
  <tr>
    <td><code>EBADF</code></td>
    <td>Indicates that a file descriptor is not valid.</td>
  </tr>
  <tr>
    <td><code>EBADMSG</code></td>
    <td>Indicates an invalid data message.</td>
  </tr>
  <tr>
    <td><code>EBUSY</code></td>
    <td>Indicates that a device or resource is busy.</td>
  </tr>
  <tr>
    <td><code>ECANCELED</code></td>
    <td>Indicates that an operation was canceled.</td>
  </tr>
  <tr>
    <td><code>ECHILD</code></td>
    <td>Indicates that there are no child processes.</td>
  </tr>
  <tr>
    <td><code>ECONNABORTED</code></td>
    <td>Indicates that the network connection has been aborted.</td>
  </tr>
  <tr>
    <td><code>ECONNREFUSED</code></td>
    <td>Indicates that the network connection has been refused.</td>
  </tr>
  <tr>
    <td><code>ECONNRESET</code></td>
    <td>Indicates that the network connection has been reset.</td>
  </tr>
  <tr>
    <td><code>EDEADLK</code></td>
    <td>Indicates that a resource deadlock has been avoided.</td>
  </tr>
  <tr>
    <td><code>EDESTADDRREQ</code></td>
    <td>Indicates that a destination address is required.</td>
  </tr>
  <tr>
    <td><code>EDOM</code></td>
    <td>Indicates that an argument is out of the domain of the function.</td>
  </tr>
  <tr>
    <td><code>EDQUOT</code></td>
    <td>Indicates that the disk quota has been exceeded.</td>
  </tr>
  <tr>
    <td><code>EEXIST</code></td>
    <td>Indicates that the file already exists.</td>
  </tr>
  <tr>
    <td><code>EFAULT</code></td>
    <td>Indicates an invalid pointer address.</td>
  </tr>
  <tr>
    <td><code>EFBIG</code></td>
    <td>Indicates that the file is too large.</td>
  </tr>
  <tr>
    <td><code>EHOSTUNREACH</code></td>
    <td>Indicates that the host is unreachable.</td>
  </tr>
  <tr>
    <td><code>EIDRM</code></td>
    <td>Indicates that the identifier has been removed.</td>
  </tr>
  <tr>
    <td><code>EILSEQ</code></td>
    <td>Indicates an illegal byte sequence.</td>
  </tr>
  <tr>
    <td><code>EINPROGRESS</code></td>
    <td>Indicates that an operation is already in progress.</td>
  </tr>
  <tr>
    <td><code>EINTR</code></td>
    <td>Indicates that a function call was interrupted.</td>
  </tr>
  <tr>
    <td><code>EINVAL</code></td>
    <td>Indicates that an invalid argument was provided.</td>
  </tr>
  <tr>
    <td><code>EIO</code></td>
    <td>Indicates an otherwise unspecified I/O error.</td>
  </tr>
  <tr>
    <td><code>EISCONN</code></td>
    <td>Indicates that the socket is connected.</td>
  </tr>
  <tr>
    <td><code>EISDIR</code></td>
    <td>Indicates that the path is a directory.</td>
  </tr>
  <tr>
    <td><code>ELOOP</code></td>
    <td>Indicates too many levels of symbolic links in a path.</td>
  </tr>
  <tr>
    <td><code>EMFILE</code></td>
    <td>Indicates that there are too many open files.</td>
  </tr>
  <tr>
    <td><code>EMLINK</code></td>
    <td>Indicates that there are too many hard links to a file.</td>
  </tr>
  <tr>
    <td><code>EMSGSIZE</code></td>
    <td>Indicates that the provided message is too long.</td>
  </tr>
  <tr>
    <td><code>EMULTIHOP</code></td>
    <td>Indicates that a multihop was attempted.</td>
  </tr>
  <tr>
    <td><code>ENAMETOOLONG</code></td>
    <td>Indicates that the filename is too long.</td>
  </tr>
  <tr>
    <td><code>ENETDOWN</code></td>
    <td>Indicates that the network is down.</td>
  </tr>
  <tr>
    <td><code>ENETRESET</code></td>
    <td>Indicates that the connection has been aborted by the network.</td>
  </tr>
  <tr>
    <td><code>ENETUNREACH</code></td>
    <td>Indicates that the network is unreachable.</td>
  </tr>
  <tr>
    <td><code>ENFILE</code></td>
    <td>Indicates too many open files in the system.</td>
  </tr>
  <tr>
    <td><code>ENOBUFS</code></td>
    <td>Indicates that no buffer space is available.</td>
  </tr>
  <tr>
    <td><code>ENODATA</code></td>
    <td>Indicates that no message is available on the stream head read
    queue.</td>
  </tr>
  <tr>
    <td><code>ENODEV</code></td>
    <td>Indicates that there is no such device.</td>
  </tr>
  <tr>
    <td><code>ENOENT</code></td>
    <td>Indicates that there is no such file or directory.</td>
  </tr>
  <tr>
    <td><code>ENOEXEC</code></td>
    <td>Indicates an exec format error.</td>
  </tr>
  <tr>
    <td><code>ENOLCK</code></td>
    <td>Indicates that there are no locks available.</td>
  </tr>
  <tr>
    <td><code>ENOLINK</code></td>
    <td>Indications that a link has been severed.</td>
  </tr>
  <tr>
    <td><code>ENOMEM</code></td>
    <td>Indicates that there is not enough space.</td>
  </tr>
  <tr>
    <td><code>ENOMSG</code></td>
    <td>Indicates that there is no message of the desired type.</td>
  </tr>
  <tr>
    <td><code>ENOPROTOOPT</code></td>
    <td>Indicates that a given protocol is not available.</td>
  </tr>
  <tr>
    <td><code>ENOSPC</code></td>
    <td>Indicates that there is no space available on the device.</td>
  </tr>
  <tr>
    <td><code>ENOSR</code></td>
    <td>Indicates that there are no stream resources available.</td>
  </tr>
  <tr>
    <td><code>ENOSTR</code></td>
    <td>Indicates that a given resource is not a stream.</td>
  </tr>
  <tr>
    <td><code>ENOSYS</code></td>
    <td>Indicates that a function has not been implemented.</td>
  </tr>
  <tr>
    <td><code>ENOTCONN</code></td>
    <td>Indicates that the socket is not connected.</td>
  </tr>
  <tr>
    <td><code>ENOTDIR</code></td>
    <td>Indicates that the path is not a directory.</td>
  </tr>
  <tr>
    <td><code>ENOTEMPTY</code></td>
    <td>Indicates that the directory is not empty.</td>
  </tr>
  <tr>
    <td><code>ENOTSOCK</code></td>
    <td>Indicates that the given item is not a socket.</td>
  </tr>
  <tr>
    <td><code>ENOTSUP</code></td>
    <td>Indicates that a given operation is not supported.</td>
  </tr>
  <tr>
    <td><code>ENOTTY</code></td>
    <td>Indicates an inappropriate I/O control operation.</td>
  </tr>
  <tr>
    <td><code>ENXIO</code></td>
    <td>Indicates no such device or address.</td>
  </tr>
  <tr>
    <td><code>EOPNOTSUPP</code></td>
    <td>Indicates that an operation is not supported on the socket.
    Note that while `ENOTSUP` and `EOPNOTSUPP` have the same value on Linux,
    according to POSIX.1 these error values should be distinct.)</td>
  </tr>
  <tr>
    <td><code>EOVERFLOW</code></td>
    <td>Indicates that a value is too large to be stored in a given data
    type.</td>
  </tr>
  <tr>
    <td><code>EPERM</code></td>
    <td>Indicates that the operation is not permitted.</td>
  </tr>
  <tr>
    <td><code>EPIPE</code></td>
    <td>Indicates a broken pipe.</td>
  </tr>
  <tr>
    <td><code>EPROTO</code></td>
    <td>Indicates a protocol error.</td>
  </tr>
  <tr>
    <td><code>EPROTONOSUPPORT</code></td>
    <td>Indicates that a protocol is not supported.</td>
  </tr>
  <tr>
    <td><code>EPROTOTYPE</code></td>
    <td>Indicates the wrong type of protocol for a socket.</td>
  </tr>
  <tr>
    <td><code>ERANGE</code></td>
    <td>Indicates that the results are too large.</td>
  </tr>
  <tr>
    <td><code>EROFS</code></td>
    <td>Indicates that the file system is read only.</td>
  </tr>
  <tr>
    <td><code>ESPIPE</code></td>
    <td>Indicates an invalid seek operation.</td>
  </tr>
  <tr>
    <td><code>ESRCH</code></td>
    <td>Indicates that there is no such process.</td>
  </tr>
  <tr>
    <td><code>ESTALE</code></td>
    <td>Indicates that the file handle is stale.</td>
  </tr>
  <tr>
    <td><code>ETIME</code></td>
    <td>Indicates an expired timer.</td>
  </tr>
  <tr>
    <td><code>ETIMEDOUT</code></td>
    <td>Indicates that the connection timed out.</td>
  </tr>
  <tr>
    <td><code>ETXTBSY</code></td>
    <td>Indicates that a text file is busy.</td>
  </tr>
  <tr>
    <td><code>EWOULDBLOCK</code></td>
    <td>Indicates that the operation would block.</td>
  </tr>
  <tr>
    <td><code>EXDEV</code></td>
    <td>Indicates an improper link.
  </tr>
</table>

#### Windows Specific Error Constants

The following error codes are specific to the Windows operating system:

<table>
  <tr>
    <th>Constant</th>
    <th>Description</th>
  </tr>
  <tr>
    <td><code>WSAEINTR</code></td>
    <td>Indicates an interrupted function call.</td>
  </tr>
  <tr>
    <td><code>WSAEBADF</code></td>
    <td>Indicates an invalid file handle.</td>
  </tr>
  <tr>
    <td><code>WSAEACCES</code></td>
    <td>Indicates insufficient permissions to complete the operation.</td>
  </tr>
  <tr>
    <td><code>WSAEFAULT</code></td>
    <td>Indicates an invalid pointer address.</td>
  </tr>
  <tr>
    <td><code>WSAEINVAL</code></td>
    <td>Indicates that an invalid argument was passed.</td>
  </tr>
  <tr>
    <td><code>WSAEMFILE</code></td>
    <td>Indicates that there are too many open files.</td>
  </tr>
  <tr>
    <td><code>WSAEWOULDBLOCK</code></td>
    <td>Indicates that a resource is temporarily unavailable.</td>
  </tr>
  <tr>
    <td><code>WSAEINPROGRESS</code></td>
    <td>Indicates that an operation is currently in progress.</td>
  </tr>
  <tr>
    <td><code>WSAEALREADY</code></td>
    <td>Indicates that an operation is already in progress.</td>
  </tr>
  <tr>
    <td><code>WSAENOTSOCK</code></td>
    <td>Indicates that the resource is not a socket.</td>
  </tr>
  <tr>
    <td><code>WSAEDESTADDRREQ</code></td>
    <td>Indicates that a destination address is required.</td>
  </tr>
  <tr>
    <td><code>WSAEMSGSIZE</code></td>
    <td>Indicates that the message size is too long.</td>
  </tr>
  <tr>
    <td><code>WSAEPROTOTYPE</code></td>
    <td>Indicates the wrong protocol type for the socket.</td>
  </tr>
  <tr>
    <td><code>WSAENOPROTOOPT</code></td>
    <td>Indicates a bad protocol option.</td>
  </tr>
  <tr>
    <td><code>WSAEPROTONOSUPPORT</code></td>
    <td>Indicates that the protocol is not supported.</td>
  </tr>
  <tr>
    <td><code>WSAESOCKTNOSUPPORT</code></td>
    <td>Indicates that the socket type is not supported.</td>
  </tr>
  <tr>
    <td><code>WSAEOPNOTSUPP</code></td>
    <td>Indicates that the operation is not supported.</td>
  </tr>
  <tr>
    <td><code>WSAEPFNOSUPPORT</code></td>
    <td>Indicates that the protocol family is not supported.</td>
  </tr>
  <tr>
    <td><code>WSAEAFNOSUPPORT</code></td>
    <td>Indicates that the address family is not supported.</td>
  </tr>
  <tr>
    <td><code>WSAEADDRINUSE</code></td>
    <td>Indicates that the network address is already in use.</td>
  </tr>
  <tr>
    <td><code>WSAEADDRNOTAVAIL</code></td>
    <td>Indicates that the network address is not available.</td>
  </tr>
  <tr>
    <td><code>WSAENETDOWN</code></td>
    <td>Indicates that the network is down.</td>
  </tr>
  <tr>
    <td><code>WSAENETUNREACH</code></td>
    <td>Indicates that the network is unreachable.</td>
  </tr>
  <tr>
    <td><code>WSAENETRESET</code></td>
    <td>Indicates that the network connection has been reset.</td>
  </tr>
  <tr>
    <td><code>WSAECONNABORTED</code></td>
    <td>Indicates that the connection has been aborted.</td>
  </tr>
  <tr>
    <td><code>WSAECONNRESET</code></td>
    <td>Indicates that the connection has been reset by the peer.</td>
  </tr>
  <tr>
    <td><code>WSAENOBUFS</code></td>
    <td>Indicates that there is no buffer space available.</td>
  </tr>
  <tr>
    <td><code>WSAEISCONN</code></td>
    <td>Indicates that the socket is already connected.</td>
  </tr>
  <tr>
    <td><code>WSAENOTCONN</code></td>
    <td>Indicates that the socket is not connected.</td>
  </tr>
  <tr>
    <td><code>WSAESHUTDOWN</code></td>
    <td>Indicates that data cannot be sent after the socket has been
    shutdown.</td>
  </tr>
  <tr>
    <td><code>WSAETOOMANYREFS</code></td>
    <td>Indicates that there are too many references.</td>
  </tr>
  <tr>
    <td><code>WSAETIMEDOUT</code></td>
    <td>Indicates that the connection has timed out.</td>
  </tr>
  <tr>
    <td><code>WSAECONNREFUSED</code></td>
    <td>Indicates that the connection has been refused.</td>
  </tr>
  <tr>
    <td><code>WSAELOOP</code></td>
    <td>Indicates that a name cannot be translated.</td>
  </tr>
  <tr>
    <td><code>WSAENAMETOOLONG</code></td>
    <td>Indicates that a name was too long.</td>
  </tr>
  <tr>
    <td><code>WSAEHOSTDOWN</code></td>
    <td>Indicates that a network host is down.</td>
  </tr>
  <tr>
    <td><code>WSAEHOSTUNREACH</code></td>
    <td>Indicates that there is no route to a network host.</td>
  </tr>
  <tr>
    <td><code>WSAENOTEMPTY</code></td>
    <td>Indicates that the directory is not empty.</td>
  </tr>
  <tr>
    <td><code>WSAEPROCLIM</code></td>
    <td>Indicates that there are too many processes.</td>
  </tr>
  <tr>
    <td><code>WSAEUSERS</code></td>
    <td>Indicates that the user quota has been exceeded.</td>
  </tr>
  <tr>
    <td><code>WSAEDQUOT</code></td>
    <td>Indicates that the disk quota has been exceeded.</td>
  </tr>
  <tr>
    <td><code>WSAESTALE</code></td>
    <td>Indicates a stale file handle reference.</td>
  </tr>
  <tr>
    <td><code>WSAEREMOTE</code></td>
    <td>Indicates that the item is remote.</td>
  </tr>
  <tr>
    <td><code>WSASYSNOTREADY</code></td>
    <td>Indicates that the network subsystem is not ready.</td>
  </tr>
  <tr>
    <td><code>WSAVERNOTSUPPORTED</code></td>
    <td>Indicates that the winsock.dll version is out of range.</td>
  </tr>
  <tr>
    <td><code>WSANOTINITIALISED</code></td>
    <td>Indicates that successful WSAStartup has not yet been performed.</td>
  </tr>
  <tr>
    <td><code>WSAEDISCON</code></td>
    <td>Indicates that a graceful shutdown is in progress.</td>
  </tr>
  <tr>
    <td><code>WSAENOMORE</code></td>
    <td>Indicates that there are no more results.</td>
  </tr>
  <tr>
    <td><code>WSAECANCELLED</code></td>
    <td>Indicates that an operation has been canceled.</td>
  </tr>
  <tr>
    <td><code>WSAEINVALIDPROCTABLE</code></td>
    <td>Indicates that the procedure call table is invalid.</td>
  </tr>
  <tr>
    <td><code>WSAEINVALIDPROVIDER</code></td>
    <td>Indicates an invalid service provider.</td>
  </tr>
  <tr>
    <td><code>WSAEPROVIDERFAILEDINIT</code></td>
    <td>Indicates that the service provider failed to initialized.</td>
  </tr>
  <tr>
    <td><code>WSASYSCALLFAILURE</code></td>
    <td>Indicates a system call failure.</td>
  </tr>
  <tr>
    <td><code>WSASERVICE_NOT_FOUND</code></td>
    <td>Indicates that a service was not found.</td>
  </tr>
  <tr>
    <td><code>WSATYPE_NOT_FOUND</code></td>
    <td>Indicates that a class type was not found.</td>
  </tr>
  <tr>
    <td><code>WSA_E_NO_MORE</code></td>
    <td>Indicates that there are no more results.</td>
  </tr>
  <tr>
    <td><code>WSA_E_CANCELLED</code></td>
    <td>Indicates that the call was canceled.</td>
  </tr>
  <tr>
    <td><code>WSAEREFUSED</code></td>
    <td>Indicates that a database query was refused.</td>
  </tr>
</table>

### libuv Constants

<table>
  <tr>
    <th>Constant</th>
    <th>Description</th>
  </tr>
  <tr>
    <td><code>UV_UDP_REUSEADDR</code></td>
    <td></td>
  </tr>
</table>

[`process.arch`]: process.html#process_process_arch
[`process.platform`]: process.html#process_process_platform
[OS Constants]: #os_os_constants