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Revision as of 14:45, 28 October 2015 by Merz (Talk | contribs) (Basic UNIX concepts)

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Basic UNIX concepts

  • Unix is an operating system, all SHARCNET systems run some variant of Unix (eg. Linux)
  • Most Unix-based systems have a GUI interface, but the command line offers more complex and abstract interactions with far less effort
  • At login the system starts a shell process for you which acts as your command line interpreter to interface with the operating system
    • Borne Again Shell ( bash ) is the default shell at SHARCNET

Common terms

  • File
    • data stored in a standard format that behaves in a certain way depending on it’s function in the system; everything is a file in Unix
  • Program
    • a file that can be executed (run)
  • Process
    • a program that is being executed (eg. your computing job is made of one or more processes)
  • Ownership
    • files/programs/processes are owned by a user and group
  • Hierarchical Directory Structure
    • files are organized in directories (folders) that can have a parent, eg. /home/$USER/sim1
    • The base of the hierarchy is root , ie: / (forward-slash)

Managing your files and processes is crucial to effectively using the systems!

Basic bash command line behavior

File systems and permissions

Managing files

Text editing

Command pipes and redirection

Shell variables, initialization, and scripts