util.isDate(object) Stability: 0 - Deprecated Returns true if the given "object" is a Date. Otherwise, returns false. const util = require('util'); util.isDate(new Date()) // true util.isDate(Date()) // false (without 'new' returns a String) util.isDate({}) // false

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

os.platform() Returns the operating system platform. Possible values are 'darwin', 'freebsd', 'linux', 'sunos' or 'win32'. Returns the value of process.platform.

path.sep The platform-specific file separator. '\\' or '/'. An example on *nix: 'foo/bar/baz'.split(path.sep) // returns ['foo', 'bar', 'baz'] An example on Windows: 'foo\\bar\\baz'.split(path.sep) // returns ['foo', 'bar', 'baz']

socket.unref() By default, binding a socket will cause it to block the Node.js process from exiting as long as the socket is open. The socket.unref() method can be used to exclude the socket from the reference counting that keeps the Node.js process active, allowing the process to exit even if the socket is still listening. Calling socket.unref() multiple times will have no addition effect. The socket.unref() method returns a reference to the socket so calls can be chained.

agent.sockets An object which contains arrays of sockets currently in use by the Agent. Do not modify.

decipher.setAuthTag(buffer) When using an authenticated encryption mode (only GCM is currently supported), the decipher.setAuthTag() method is used to pass in the received authentication tag. If no tag is provided, or if the cipher text has been tampered with, decipher.final() with throw, indicating that the cipher text should be discarded due to failed authentication.

message.httpVersion In case of server request, the HTTP version sent by the client. In the case of client response, the HTTP version of the connected-to server. Probably either '1.1' or '1.0'. Also message.httpVersionMajor is the first integer and message.httpVersionMinor is the second.

readline.clearLine(stream, dir) Clears current line of given TTY stream in a specified direction. dir should have one of following values: -1 - to the left from cursor 1 - to the right from cursor 0 - the entire line

buf.writeFloatBE(value, offset[, noAssert])