3. w To edit file [vi – gedit – copy edit file without read it]

4. x To execute an executable file (c file should have x to be

6. this directory (ls dir need read permission)

7. w To create or remove 0r rename file or dir from the

8. directory

9. x To cd to this directory you need execute

11. Octal

12. Symbols:

13. u: Owner g: group o: others

14. r: read w: write x: execute

15. u=rw,g=r,o=r give owner read/write & g read & others read

16. u+x,g+x,o+x append execute for all

17. u-rw remove read & write permission from owner

18. a+r append execute for all (a) equivalent to u&g&o

19. Octal:

20. Owner Owner’s group Others

22. R W X R W X R W X Denied: 0

23. Exist: 1

24. rw- r- - r- - : 110 100 100 : 644

26. How to view mask??

27. # umask

28. 0022 Default

29. How to change mask??

30. Symbols:

31. # umask a=rwx

32. So any file will be created will have permission rw-rw-rw-

33. & any directory will be created will have permission rwxrwxrwx

34. # umask

35. 0000 full permission

36. Octal:

37. # umask 000 000 Complement of required permissions

38. So any file will be created will have permission rw-rw-rw-

39. & any directory will be created will have permission rwxrwxrwx

40. Notes:

43. Last line mode: :

44. Esc: To shift to the command mode

45. Command:

46. k

47. hl

49. j

50. i To turn to editing (inserting) mode

51. a To turn to editing (appending) mode

52. A To turn to editing mode and go to the end of the line

53. I To turn to editing mode and go to the beginning of the line

54. 0 To go to the beginning of line

55. $ To go to the end line

56. G To go to the end of file

57. H To go to the begin of file

58. R Replace

59. x Delete the character on cursor

60. X Delete the character at the left of the cursor

61. :w Save file

62. :wq save and quit equivalent to ZZ

63. :w filename Save as filename

64. :q To quit refuse to quit if no save

65. :q! To force to quit without saving

66. yy To copy current line you are standing on

67. dd cut current line you are standing on

68. p paste below the line you are standing on

69. P Paste above the line you are standing on

70. y#w copy # words and then paste them where you want

71. d#w cut # words and then paste them where you want

72. O begin to write above line you are standing on

73. o begin to write below line you are standing on

74. / text Search for the text n: next occurance N: previous occurance

75. ~ Switch from lower case to upper case & vice versa for

76. Highlighted word

77. u undo “but just once” U undo all changes happen to line

78. . redo

79. r replace

80. :# go to line #

81. #j go to line # relative to current line

82. :#d cut line #

83. dH cut from line you r standing on till beginning of file(up)

84. d0 cut from where you r standing on till end of line == D

85. dG cut from line you r standing on till end of file(down)

86. d$ cut from where you r standing on till begin of line

87. :#dd 3dd cut line you r standing on and 2 lines below this line

88. :#y copy line #

89. yH copy from line you r standing on till beginning of file(up)

90. y0 copy from where you r standing on till end of line

91. yG copy from line you r standing on till end of file(down)

92. y$ copy from where you r standing on till begin of line

93. :#yy 3yy copy line you r standing on and 2 lines below this line

94. :set number To numbering the file

95. :set nonu To turn numbering of file off

96. :set showmode To show mode {command mode } show nothing

97. a append mode

98. i insert mode

99. R replace mode

103. Once this command is executed an entry will be added to /etc/group