3i Infotech Papers: Sample Questions 820 - 821 of 1245

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Question number: 820

» Operating System » Unix

Essay Question▾

Describe in Detail

How can a parent and child process communication?

Explanation

Define create new process.

Define Create New Process.

Define create new process.

  • A parent and child can communicate using normal inter-process communication schemes- in addition they have special ways to communication which take advantages of their parent child relationship.

  • After forking the process, child process inherits all properties of parent, also pipe.

  • The child inherits file descriptors from its parent, if parent opens two ends of a pipe then after fork, parent can chose one end and the child choses the other end of the pipe.

  • This is done using popen () routine to run a child program.

  • Parent can store the file descriptor returned from popen () -child and parent processes can use it as stdin, and stdout.

  • In addition, child process inherits memory segments mapped anonymously by the parent- not accessible from unrelated processes.

Question number: 821

» Basic CS » Networks

Short Answer Question▾

Write in Short

What is MAC address?

Explanation

  • The unique address for a device identified at the Media Access Control layer in the network architecture.

  • Used by the Media Access Control sub-layer of the Data-Link Layer of telecommunication protocols.

  • Different MAC exist for each physical device type

  • Usually stored in ROM on the network adapter card.

  • A hardware identification number that uniquely identifies each device on a network- manufactured into every network card, ethernet card, or Wi-Fi card.

  • Reliable way to identify senders and receivers of data on the network.

  • They are usually written in one of the below three formats:

  1. MM: MM: MM: SS: SS: SS
  2. MM: MM-MM-SS-SS-SS
  3. MMM. MMM. SSS. SSS