70 Frequently-asked Basic UNIX Interview Questions With Answers – Download PDF file Also you can Download this “UNIX Interview Questions With Answers” as a PDF file 1.How do you execute one program from within another?The system calls used for low-level process creation are execlp() and execvp().The execlp call overlays the existing program with the new one , runs that and exits.Shared Memory: This is the fastest of all IPC schemes.The memory to be shared is mapped into the address space of the processes (that are sharing).Allows the greater process size than the available physical memory.Demand paging systems handle the memory more flexibly. What is major difference between the Historic Unix and the new BSD release of Unix System V in terms of Memory Management?
Swapping: Whole process is moved from the swap device to the main memory for execution.
They are, – Page table entries, – Disk block descriptors, – Page frame data table (pfdata), – Swap-use table. Kernel follows Round Robin scheme choosing a swap device among the multiple swap devices in Unix System V. Thus, device files and other files are named and accessed in the same way.
A ‘regular file’ is just an ordinary data file in the disk.
Historic Unix uses Swapping – entire process is transferred to the main memory from the swap device, whereas the Unix System V uses Demand Paging – only the part of the process is moved to the main memory.
Historic Unix uses one Swap Device and Unix System V allow multiple Swap Devices. In what way the Fault Handlers and the Interrupt handlers are different? Protection fault refers to the process accessing the pages, which do not have the access permission.