System Programming MCQ Questions Answers

1. An expert system uses _________ , or rules of thumb, to arrive at conclusions or make suggestions.

2. _____ are the systems special characteristics that appeal to users.

3. Placing a structure within another structure is called ____ structures.

4. Effect of appending an ampersand ('&') at the end of a shell command?

5. Which ones are true of typical Unix like systems?

6. Which compiler option links the standard math library to the executable?

7. Which system call can be used to change process scheduling priority?

8. How do two threads synchronize access to shared data in a multi threaded application?

9. Which command can be used to install the native software package SOFTpkg on a Solaris system?

10. If a write system call fails and if errno is set to EFAULT, what does it signify?

11. A process opens a file and forgets to close the file descriptor when it exits. What is the result?

12. Where are the DNS and search domains specified?

13. Which C header needs to be included for socket programming?

14. Which shell operator is used to send the standard output of the first command to the standard input of the second command?

15. Which system call creates a named socket?

16. Which socket system call creates a Unix Domain Socket connection?

17. If a process is terminated due to a SEGFAULT on a Solaris 9 system, what is the name of the core file that is created?

18. Which system call can be used to create device special files?

19. Outcome of attempting an ioctl system call on a block device file?

20. Which IO mechanism allows greater performance to concurrent IO-intensive applications?

21. Which command can be used to compile a C file called 'test.c' into an executable called 'test'?

22. Which system call is specific to debugging?

23. Which command can be used to create a static (archive) library?

24. Which system calls can be used to get the metadata of a file?

25. Which one creates an IPC message channel?

26. Which one is employed by the operating system to speed up file IO on a Solaris system.

27. Name of the standard linker on Unix?

28. Which block size results in the best read/write performance for an IO intensive application?

29. By convention, which signal causes a daemon to reload its configuration?

30. How do threads created using pthread library share data between themselves efficiently?

31. Which segment within the process address space are unique to each thread?

32. What is the network byte order in Unix?

33. Which gcc option can be used to generate a position independent code on a Linux system?

34. Which call is used to initiate a socket connection to a target address?

35. Which shell parameter contains the return value of the previously executed shell command?

36. On Linux, the pthread_create interface does not use the fork system call to create threads.

37. If a process executes the following C code on a Linux system, what is the outcome?

38. What does the open system call return upon success?

39. Which sequence creates a socket based connection for communication?

40. A C program 'domath.c' utilizes the math library. Which command correctly creates the corresponding executable 'domath'?

41. Effect of setting the 'sticky' bit on an application's executable image?

42. How many bytes of a file of size 1023 will be read by the following piece of code?

43. Which ksh trap sequence causes the function 'handler' to be executed when the script exits?

44. Which command can be used to list all the active TCP connections only on a Linux system?

45. Which command can be used on a Linux system to configure a network interface (card)?

46. Which command can be used on a Linux system to kill process 8977 and all its children?

47. Default file descriptor used for the error outputs of a process?

48. Which command can be used to generate a listing of all the shared libraries that an executable needs?

49. Which shell command is useful in single stepping through a shell script?

50. Which system call is used to send a signal to another process?

51. Typical system calls the Unix shell invokes when it has to execute a new command?

52. Which redirects the standard error output of a command to the log file 'error.log'?

53. Shared libraries increase an application's disk size?

54. What does the '-pg' option of the Unix compiler do?

55. Which compiler options generates an assembler output file?

56. How is the value of the shell environment variable IFS changed to comma (',')?

57. Which IPC shared memory sequences is correct?

58. Which library provides the POSIX thread implementation on Solaris?

59. How does a programmer distinguish a child from its parent process following a fork system call?

60. Effect of executing the following system call on the file ''test.txt''?

61. Which IPC message operation is performed to setup communication between arbitrary processes?

62. Which library routine is used to translate the numeric system call error code to a human readable text error message?

63. Which shell operator redirects the standard input of the command being executed?

64. Which option specifies a non standard library path during linking?

65. Which option of the compiler is turned on to generate additional debug information (like the source code) for debugging an application?

66. Which gcc compiler option turns on optimization?

67. The library routine printf does not use any system calls.

68. If a process is hung in the kernel context, sending it a SIGKILL will _____.

69. Which one is true of Unix system calls?

70. Which system call increases the process priority?

71. Which sequence prints all the second column fields of an input file 'values.txt'?

72. Effect of issuing a '$c' command at the adb prompt during a debugging session on a Solaris 9 system?

73. Which command generates a listing of the system calls being executed by a program on Solaris?

74. Which system call is the most memory efficient method of reading a file?

75. What does the command do to the process with pid 12345?

76. Command to list the shared libraries used by an executable?

77. Ignoring the setup cost for each of the System V IPC mechanisms, which one is the most efficient?

78. Which signal cannot be ignored by a process?

79. Effect of a process executing an unlink system call while another process has opened the same file?

80. What does the 'open' system call return to the caller?

81. Threads created via pthread_create need to first set up shared memory using shmop before they can share data.

82. What does the command 'mknod temp p' do?

83. Which utility is used to search out regular expressions in the input?

84. If a process has locked a System V Semaphore and receives a SIGKILL signal, which one is true?

85. How to debug the process '123' and program 'test' on a Linux system?

86. Which utility is used to generate a core file of a process on Linux?

87. How to to allocate and use memory on a Unix system?

88. How to inspect the system call arguments of a Linux process?

89. Which utility would you use on a standard Linux system to debug a running application?

90. Which environment variable specifies the shared library search path?

91. Which signals are used by the Unix shell to implement job control?

92. Which Linux command can be used to identify the processes consuming maximum resources (CPU, Memory)?

93. Which method can be used as a communication mechanism between two unrelated processes?

94. Which gdb command can be used to obtain the stack trace of all the threads of a multi threaded program running on Linux?

95. Which are true of Unix system calls?

96. Which system call can be used to send a message via a connected socket?

97. What does this code do: BOOL sharedLockSuccess = NO; NSLock *aMutex; : sharedLockSuccess = [aMutex lockWhenCondition:1 beforeDate:[NSDate dateWithTimeIntervalSinceNow:(NSTimeInterval)3600]]; :

98. Recently your office's UNIX tool-chain was updated. Now, code that previously used to build and run still builds without any warnings or errors but displays load-time errors due to symbols not found in shlibs. You have ensured that all necessary shared libraries are present in the path 'pointed to' by the appropriate environment variable. Which is true?

99. It is not possible to set the sticky bit of a file when creating it. Therefore it is necessary to create the directory and then set the sticky bit by executing: mkdir(“/tmp/dir”, 0744); chmod(“/tmp/dir”, 07744). Why?

100. In a Unix toolchain, which one of these pairs does not fit with the others?