Basic UNIX commands

• man - manual/help
• pwd - print working/current directory
• ls - list files
• ls -l - lists files in 'long format', which contains lots of useful information, e.g. the exact size of the file, who owns the file and who has the right to look at it, and when it was last modified
• cd - change directory
• mkdir [dir] - creates dir
• rmdir [dir] - removes dir
• more [options] file(s) - Display contents of files
• less [options] file(s) - Display contents of files
  Useful commands while viewing a file with 'more' or 'less':
  • <spacebar> - scroll forward one page
  • ^b (control-b) - scroll backward one page
  • /<text> - search for string
  • n - find next occurence of string
  • N - find previous occurence of string (search for string in opposite direction)*
  • g - go to the beginning of the file*
  • G - go to the end of the file*
  • v - edit the current file with 'vi'*
  • :n - go to the next file*
  • :p - go to the previous file*
  • q - quit
  *works in 'less', not 'more'
• grep [options] <pattern> [files] - search inside files for the given pattern
  Useful options:
  • -i - ignore case
  • -r or -R - search files in directories/subdirectories recursively
  • -v - nvert match: select non-matching lines
• tail [options] [filenames] - show tail/end of file
• tail -f temp.log - follow/monitor the file, display the last 10 lines of temp.log and append new lines to the display as new lines are added to temp.log
• vi filename - edit the file
  Modes:
  • command mode - letters of the keyboard will be interpreted as commands
  • insert mode - letters of the keyboard will type or edit text
  Useful commands:
  • x - deletes the character the cursor is under
  • dd - deletes the line the cursor is on
  • a - append after the cursor
  • i - insert before the cursor
  • ESC - non edit mode
  • :wq - saves the current changes and exits vi
  • :w - saves the current changes but does not exit vi
  • :q - exits vi without saving any change

References:
http://claymore.rfmh.org/public/computer_resources/unix_commands.html
http://mally.stanford.edu/~sr/computing/basic-unix.html
http://cmgm.stanford.edu/classes/unix/vi.html
http://en.wikipedia.org
http://www.ccsf.edu/Pub/Fac/vi.html