OS Modules

os module is used to get operating system related properties. This includes os architecture, RAM, number of processors, network interfaces, os platform, os type etc.

OS Modules is a build in module in node js.

OS Modules Code

         
   
    const os=require('os');
    

OS Arcitecture

os.arch method returns the architecture of operating system. The possible values are 'arm', 'arm64', 'ia32', 'mips', 'mipsel', 'ppc', 'ppc64', 's390', 's390x', 'x32', and 'x64'.

X64
         
   
    const os=require('os');
    const arch=os.arch();
    

OS CPUS

os.cpus method returns the information of each CPU Core. This method returns an array of objects having information about each CPU Core.

[
  {
    model: 'Intel(R) Core(TM) i5-5250U CPU @ 1.60GHz',
    speed: 1600,
    times: { user: 9886220, nice: 0, sys: 5667630, idle: 53688060, irq: 0 }
  },
  {
    model: 'Intel(R) Core(TM) i5-5250U CPU @ 1.60GHz',
    speed: 1600,
    times: { user: 3471770, nice: 0, sys: 2076480, idle: 63685880, irq: 0 }
  },
  {
    model: 'Intel(R) Core(TM) i5-5250U CPU @ 1.60GHz',
    speed: 1600,
    times: { user: 9939290, nice: 0, sys: 4517010, idle: 54777840, irq: 0 }
  },
  {
    model: 'Intel(R) Core(TM) i5-5250U CPU @ 1.60GHz',
    speed: 1600,
    times: { user: 3209900, nice: 0, sys: 1871270, idle: 64152950, irq: 0 }
  }
]     
         
   
    const os=require('os');
    const cpus=os.cpus();
    

To get information of each individual cpu core, use for each method of above array.

         
   
    const os=require('os');
    const cpus=os.cpus();
    
    cpus.forEach(function(i){
        console.log(i);
    })
    

OS Memory

OS Memory method can check total memory and free memory. Memory stands for Random access memory (RAM). The units for memory is in bytes.

8589934592
3095019520

    const os=require('os');
    
    console.log(os.totalmem());
    console.log(os.freemem());

Total Memory

Total Memory is the actual size of RAM. To get Total, memory, use os.totalmem() method. The default unit is in bytes. To get RAM size in GB, divide it by 1073741824, i.e. (1024*1024*1024). To get RAM size in MB, divide it by 1048576, i.e (1024*1024).

Total RAM in GBs

8 GB

    const os=require('os');
    
    console.log((os.totalmem()/1073741824)+ "GB" );

Total RAM in MBs

8192 MB

    const os=require('os');
    
    console.log((os.totalmem()/1048576)+ "MB");

Free Memory

os.freemem method is used to check free memory out of total memory.

Check free memory

18710528

    const os=require('os');
    
    console.log(os.freemem());

os.networkInterfaces

os.networkInterfaces method returns an object containing information related to network interfaces assigned to the device. That includes mac id, ip address etc.

{
  lo: [
    {
      address: '127.0.0.1',
      netmask: '255.0.0.0',
      family: 'IPv4',
      mac: '00:00:00:00:00:00',
      internal: true,
      cidr: '127.0.0.1/8'
    },
    {
      address: '::1',
      netmask: 'ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff',
      family: 'IPv6',
      mac: '00:00:00:00:00:00',
      scopeid: 0,
      internal: true,
      cidr: '::1/128'
    }
  ],
  eth0: [
    {
      address: '192.168.1.108',
      netmask: '255.255.255.0',
      family: 'IPv4',
      mac: '01:02:03:0a:0b:0c',
      internal: false,
      cidr: '192.168.1.108/24'
    },
    {
      address: 'fe80::a00:27ff:fe4e:66a1',
      netmask: 'ffff:ffff:ffff:ffff::',
      family: 'IPv6',
      mac: '01:02:03:0a:0b:0c',
      scopeid: 1,
      internal: false,
      cidr: 'fe80::a00:27ff:fe4e:66a1/64'
    }
  ]
}    

    const os=require('os');
    
    console.log(os.networkInterfaces());

OS Platform

os.platform method returns a string containing platform of operating system. That can be "darwin", "win32", "linux" etc.

darwin

    const os=require('os');
    
    console.log(os.platform());

OS Type

os.type method returns a string containing name of operating system. That can be "Darwin", "Windows_NT", "Linux" etc.

Darwin

    const os=require('os');
    
    console.log(os.type());

OS uptime

os.uptime method returns system uptime in seconds.

370108s secs
6168.466 mins
102.807 hours

    const os=require('os');
    
    console.log(os.uptime()+" secs");
    console.log((os.uptime()/60)+ " mins");
    console.log((os.uptime()/3600)+ " hours");

OS userInfo

os.userInfo method returns an object with information of user like, uid, gid, username, home directory and default shell.

{
  uid: 501,
  gid: 20,
  username: 'avinashmalhotra',
  homedir: '/Users/avinashmalhotra',
  shell: '/bin/zsh'
}    

    const os=require('os');
    
    console.log(os.userInfo())