Namespace node.process

The process object is a global object and can be accessed from anywhere. It is an instance of EventEmitter.

Field Summary
Field Attributes Field Name and Description
static  
node.process.ARGV
static  
node.process.argv
An array containing the command line arguments.
static  
node.process.env
An object containing the user environment.
static  
node.process.ENV
static  
node.process.execPath
This is the absolute pathname of the executable that started the process.
static  
node.process.installPrefix
A compiled-in property that exposes NODE_PREFIX.
static  
node.process.mainModule
static  
node.process.pid
The PID of the process.
static  
node.process.platform
What platform you're running on.
static  
node.process.stderr
A writable stream to stderr.
static  
node.process.stdin
A Readable Stream for stdin.
static  
node.process.stdout
A Writable Stream to stdout.
static  
node.process.title
Getter/setter to set what is displayed in 'ps'.
static  
node.process.version
A compiled-in property that exposes NODE_VERSION.
static  
node.process.versions

Method Summary

Method Attributes Method Name and Description
static  
node.process.addListener(type, listener)
static  
node.process.assert()
static  
node.process.binding()
static  
node.process.chdir()
Changes the current working directory of the process or throws an exception if that fails.
static  
node.process.compile()
static  
node.process.createChildProcess()
static  
node.process.cwd()
Returns the current working directory of the process.
static  
node.process.debug()
static  
node.process.dlopen()
static  
node.process.emit(type)
static  
node.process.error()
static  
node.process.exit(code)
Ends the process with the specified code.
static  
node.process.getgid()
Gets the group identity of the process.
static  
node.process.getuid()
Gets the user identity of the process.
static  
node.process.inherits()
static  
node.process.kill(pid, sig)
Send a signal to a process.
static  
node.process.listeners(type)
static  
node.process.memoryUsage()
Returns an object describing the memory usage of the Node process.
static  
node.process.mixin()
static  
node.process.nextTick(callback)
On the next loop around the event loop call this callback.
static  
node.process.on(type, listener)
static  
node.process.once(type, listener)
static  
node.process.openStdin()
static  
node.process.reallyExit()
static  
node.process.removeAllListeners(type)
static  
node.process.removeListener(type, listener)
static  
node.process.setgid()
Sets the group identity of the process.
static  
node.process.setMaxListeners(n)
static  
node.process.setuid()
Sets the user identity of the process.
static  
node.process.umask()
Sets or reads the process's file mode creation mask.
static  
node.process.unwatchFile()
static  
node.process.watchFile()

Field Detail

static node.process.ARGV
static node.process.argv
An array containing the command line arguments. The first element will be 'node', the second element will be the name of the JavaScript file. The next elements will be any additional command line arguments.
    // print process.argv
    process.argv.forEach(function (val, index, array) {
      console.log(index + ': ' + val);
    });
This will generate:
    $ node process-2.js one two=three four
    0: node
    1: /Users/mjr/work/node/process-2.js
    2: one
    3: two=three
    4: four
static node.process.env
An object containing the user environment. See environ(7).
static node.process.ENV
static node.process.execPath
This is the absolute pathname of the executable that started the process. Example:
    /usr/local/bin/node
static node.process.installPrefix
A compiled-in property that exposes NODE_PREFIX.
    console.log('Prefix: ' + process.installPrefix);
static node.process.mainModule
static node.process.pid
The PID of the process.
    console.log('This process is pid ' + process.pid);
static node.process.platform
What platform you're running on. 'linux2', 'darwin', etc.
    console.log('This platform is ' + process.platform);
static node.process.stderr
A writable stream to stderr. Writes on this stream are blocking.
static node.process.stdin
A Readable Stream for stdin. The stdin stream is paused by default, so one must call process.stdin.resume() to read from it. Example of opening standard input and listening for both events:
    process.stdin.resume();
    process.stdin.setEncoding('utf8');

    process.stdin.on('data', function (chunk) {
      process.stdout.write('data: ' + chunk);
    });

    process.stdin.on('end', function () {
      process.stdout.write('end');
    });
static node.process.stdout
A Writable Stream to stdout. Example: the definition of console.log
    console.log = function (d) {
      process.stdout.write(d + '\n');
    };
static node.process.title
Getter/setter to set what is displayed in 'ps'.
static node.process.version
A compiled-in property that exposes NODE_VERSION.
    console.log('Version: ' + process.version);
static node.process.versions

Method Detail

  • static node.process.addListener(type, listener)
    Parameters:
    {string} type
    {string} listener
  • static node.process.assert()
  • static node.process.binding()
  • static node.process.chdir()
    Changes the current working directory of the process or throws an exception if that fails.
        console.log('Starting directory: ' + process.cwd());
        try {
          process.chdir('/tmp');
          console.log('New directory: ' + process.cwd());
        }
        catch (err) {
          console.log('chdir: ' + err);
        }
    
  • static node.process.compile()
  • static node.process.createChildProcess()
  • static node.process.cwd()
    Returns the current working directory of the process.
        console.log('Current directory: ' + process.cwd());
    
  • static node.process.debug()
  • static node.process.dlopen()
  • static node.process.emit(type)
    Parameters:
    {string} type
  • static node.process.error()
  • static node.process.exit(code)
    Ends the process with the specified code. If omitted, exit uses the 'success' code 0. To exit with a 'failure' code:
        process.exit(1);
    
    The shell that executed node should see the exit code as 1.
    Parameters:
    {string} code
  • static node.process.getgid()
    Gets the group identity of the process. (See getgid(2).) This is the numerical group id, not the group name.
        console.log('Current gid: ' + process.getgid());
    
  • static node.process.getuid()
    Gets the user identity of the process. (See getuid(2).) This is the numerical userid, not the username.
        console.log('Current uid: ' + process.getuid());
    
  • static node.process.inherits()
  • static node.process.kill(pid, sig)
    Send a signal to a process. pid is the process id and signal is the string describing the signal to send. Signal names are strings like 'SIGINT' or 'SIGUSR1'. If omitted, the signal will be 'SIGTERM'. See kill(2) for more information. Note that just because the name of this function is process.kill, it is really just a signal sender, like the kill system call. The signal sent may do something other than kill the target process. Example of sending a signal to yourself:
        process.on('SIGHUP', function () {
          console.log('Got SIGHUP signal.');
        });
    
        setTimeout(function () {
          console.log('Exiting.');
          process.exit(0);
        }, 100);
    
        process.kill(process.pid, 'SIGHUP');
    
    Parameters:
    {string} pid
    {string} sig
  • static node.process.listeners(type)
    Parameters:
    {string} type
  • static node.process.memoryUsage()
    Returns an object describing the memory usage of the Node process.
        var util = require('util');
    
        console.log(util.inspect(process.memoryUsage()));
    
    This will generate:
        { rss: 4935680,
          vsize: 41893888,
          heapTotal: 1826816,
          heapUsed: 650472 }
    
    heapTotal and heapUsed refer to V8's memory usage.
  • static node.process.mixin()
  • static node.process.nextTick(callback)
    On the next loop around the event loop call this callback. This is *not* a simple alias to setTimeout(fn, 0), it's much more efficient.
        process.nextTick(function () {
          console.log('nextTick callback');
        });
    
    Parameters:
    {function(Error?|...[*]):undefined=} callback
  • static node.process.on(type, listener)
    Parameters:
    {string} type
    {string} listener
  • static node.process.once(type, listener)
    Parameters:
    {string} type
    {string} listener
  • static node.process.openStdin()
  • static node.process.reallyExit()
  • static node.process.removeAllListeners(type)
    Parameters:
    {string} type
  • static node.process.removeListener(type, listener)
    Parameters:
    {string} type
    {string} listener
  • static node.process.setgid()
    Sets the group identity of the process. (See setgid(2).) This accepts either a numerical ID or a groupname string. If a groupname is specified, this method blocks while resolving it to a numerical ID.
        console.log('Current gid: ' + process.getgid());
        try {
          process.setgid(501);
          console.log('New gid: ' + process.getgid());
        }
        catch (err) {
          console.log('Failed to set gid: ' + err);
        }
    
  • static node.process.setMaxListeners(n)
    Parameters:
    {string} n
  • static node.process.setuid()
    Sets the user identity of the process. (See setuid(2).) This accepts either a numerical ID or a username string. If a username is specified, this method blocks while resolving it to a numerical ID.
        console.log('Current uid: ' + process.getuid());
        try {
          process.setuid(501);
          console.log('New uid: ' + process.getuid());
        }
        catch (err) {
          console.log('Failed to set uid: ' + err);
        }
    
  • static node.process.umask()
    Sets or reads the process's file mode creation mask. Child processes inherit the mask from the parent process. Returns the old mask if mask argument is given, otherwise returns the current mask.
        var oldmask, newmask = 0644;
    
        oldmask = process.umask(newmask);
        console.log('Changed umask from: ' + oldmask.toString(8) +
                    ' to ' + newmask.toString(8));
    
  • static node.process.unwatchFile()
  • static node.process.watchFile()