basic linux command set

  • egrep [^letter]
  • ^ means after that letter all lines are highlighted
  • egrep[letter$]
  • $ means before that letter all lines are highlighted
  • egrep[^letter$]
  • inbetween letters are highlightedr
  • -p stands for parent directory it will create folder in home elpthat set
  • if u not use  -p it will not create folder at home by default
  • rm is used to delete only files not whole folder
  • rm -rf is used to remove directory recursively without  asking permission

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