Basic CS-Operating System [3i Infotech Placement]: Sample Questions 78 - 79 of 89
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Question 78
Explanation
- Mutant provides kernel mode or user mode in Windows NT, mutual exclusion with the notion of ownership.
- Window NT is a Microsoft window personal computer operating system it is designed for users and businesses needing capacity.
- The server is designed for business machines that need to provide services for network-attached computers.
- Internal part of biology that mutation in a gene, it is possible to establish the normal function of the gene.
User Mode:
- Executing code has no ability to directly access hardware or memory.
- When run code in user mode delegate to system API to access hardware or memory.
- The protection by this sort of isolation, crashes in user mode is always recoverable.
Kernel mode:
- The executing code has complete and unrestricted access to the underlying hardware.
- Execute any CPU instruction and reference any memory address.
- Generally reserved for the lowest-level.
Question 79
Write in Short Short Answer▾
Which function should be used to free the memory allocated by calloc () ?
EditExplanation
- free () is a function used to free the memory allocated dynamically, by both malloc and calloc functions.
- free (ptr) ;
- ptr is a pointer to a memory block which has already been created by malloc or calloc.
- The memory we give back by calling free () is immediately available to other parts of program.
- When we program exits, any allocated memory not freed is automatically released by the operating system.
- Used data is prepended to the allocated block to manage the heap. If memory pointed to was not allocated by a heap allocation function as malloc () or calloc () , then the data preceding the block will be management data.