LINUX Operating System Notes | B.Sc. (Computer Science) Semester 1 | Mumbai University | munotes

Contents

Module I

1. What an Operating System Is, and Where Linux Fits 1
2. The History of Linux: Unix, MINIX, GNU and a Student's Kernel 4
3. Linux Distributions, and Why There Are So Many 7
4. The Architecture of a Unix or Linux System 10
5. The Features of Unix and Linux 13
6. Installing Ubuntu: Making the USB and Booting From It 17
7. Installing Ubuntu: The Installer, Step by Step 20
8. Installing Software: App Center, Synaptic and apt 23
9. Packages, Repositories and the Software Worth Having 27
10. Administering System and User Settings 30
11. Keyboard Shortcuts, and the Story of Unity 33
12. The Terminal: Where the Rest of This Book Happens 36
13. Starting the Shell: Which Shell Are You Running 39
14. The Shell Prompt, and How to Change It 42
15. The Structure of a Command: Options and Arguments 44
16. The File System: One Tree That Starts at / 47
17. What Each Top-Level Directory Holds 50
18. Paths: Absolute, Relative, Dot, Dot Dot and Tilde 53
19. man Pages: Reading the Manual 55
20. The Other Documentation: help, --help, info and apropos 58
21. pwd and cd: Moving Around the Tree 61
22. ls: Listing What Is There 63
23. ls -l: Reading the Long Listing 65
24. mkdir and rmdir: Making and Removing Directories 68
25. touch: Making a File, and Changing Its Times 70
26. find: Searching the Tree 73
27. du, df and stat: How Much Space, and What Exactly Is This File 77
28. cat: Reading, Making and Joining Files 80
29. more and less: Reading a File That Will Not Fit 82
30. cp: Copying Files and Directories 84
31. mv: Moving and Renaming 86
32. rm: Removing, and Why There Is No Undo 88
33. file: What Kind of File Is This 91
34. wc: Counting Lines, Words and Characters 93
35. od: Looking at the Bytes Inside a File 95
36. cmp, diff and comm: Comparing Two Files 98
37. gzip and gunzip: Compressing One File 101
38. zip and unzip: The Archive Windows Can Open 104
39. tar: Packing a Whole Directory Into One File 106
40. ln: Hard Links and Symbolic Links 109
41. cal and date: The Calendar and the Clock 112
42. echo and printf: Printing a Line 116
43. who, whoami, uname and hostname: Who and Where Am I 118
44. tty and stty: The Terminal Itself 121
45. passwd: Changing Your Password 124
46. script: Recording a Session, Which Is How the Journal Is Kept 127
47. history, alias, which and clear: Working Faster 130
48. Environment Variables: PATH, HOME and export 133
49. File Permissions: Who Can Do What 137
50. Reading the Ten Characters of ls -l 140
51. Users and Groups 143
52. chmod: Changing Permissions 146
53. chown and chgrp: Changing the Owner and the Group 149
54. umask: The Permissions a New File Is Born With 152
55. The Special Bits: setuid, setgid and the Sticky Bit 155

Module II

1. Understanding Linux Security 159
2. root: What the Superuser Can Do 163
3. sudo: Borrowing root for One Command 166
4. Working With Passwords 169
5. ssh: Logging In to Another Machine 173
6. Keys Instead of Passwords, and Copying Files With scp 177
7. who, whoami and w: Who Is On This Machine 181
8. ping: Is That Machine There 184
9. telnet and ftp: The Old Pair, and What Replaced Them 188
10. ip, hostname, wget and curl 191
11. Standard Input, Standard Output and Standard Error 195
12. Redirection: >, >>, < and 2> 199
13. Pipes: Joining Commands Together 202
14. head and tail: The Beginning and the End 205
15. cut and paste: Columns In and Out 208
16. sort: Putting Lines in Order 211
17. uniq: Collapsing and Counting Repeats 214
18. tr: Translating and Deleting Characters 217
19. tee: Saving the Middle of a Pipeline 220
20. Regular Expressions: The Basic Set 223
21. Extended Regular Expressions 228
22. grep and the grep Family 232
23. vi: The Three Modes 236
24. vi: Moving, Editing, Searching and Saving 242
25. sed: The Stream Editor 249
26. awk: Records, Fields and Actions 254
27. Your First Shell Script 260
28. Variables, Quoting and Command Substitution 265
29. read: Asking the User a Question 270
30. exit and the Exit Status 274
31. Arithmetic: expr, $(( )) and bc 278
32. test and [ ]: Asking Questions About Files, Strings and Numbers 282
33. if, elif and else 287
34. Logical Operators: &&, || and ! 290
35. case and Functions: the Other Control Structures 294
36. The for Loop 299
37. The while and until Loops 303
38. Redirection Inside a Script, and Here Documents 307
39. Creating Your Own Redirection: exec and File Descriptors 311
40. Processes: What One Is, and ps 315
41. Foreground, Background and Jobs 319
42. kill and Signals 323
43. nice and renice: Choosing a Priority 327
44. top and the Other Process Tools 330
45. at and batch: Running a Command Once, Later 334
46. cron and the crontab: Running a Command Again and Again 339
47. Installing the C and C++ Compilers 344
48. A First C Program on Linux 348
49. Installing Java, and a First Java Program 353
50. Python on Linux, and a Virtual Environment 357

Module J The journal and the practical examination

1. Keeping the Certified Journal 361
2. The Practical Examination: What Q.1 and Q.2 Look Like 365
3. Twelve Practicals on Module 1, Worked 369
4. Twelve Practicals on Module 2, Worked 376
5. The Viva: What You Will Be Asked, and the Answer 383