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Useful Linux Commands - III


  1. To know your hostname type
    1. hostname
  2. To know the shell we are working in
    1. ps -p $$
      1. This command would give a result:
      2. PID TTY          TIME CMD
      3. 15362 pts/3    00:00:00 zsh
    2. echo $SHELL
      1. This command would give a result like: /bin/zsh
  3. Please note that once you export your PATH variable or any other env variable, you should restart your terminal to see the changes
  4. To create links between the files we can use "ln"
  5. To view the current processes which are Running: 
    1. ps -ef | more
  6. To find out how much free memory (RAM) we have on our linux box:
    1. free
      1. This command will give the used, swap, free memory on our linux box
      2. Also the output is in bytes
    2. free -g
      1. This command will give the used, swap, free memory on our linux box in GB's
  7. To find out the disk space usage data: 
    1. df -k 
      1. This commands gives output in bytes
    2. df -h 
      1. This gives the output in GB's 
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