Ans: Who | echo "total users `who|wc -l`"ls | grep -c "poem" | tee filename.txtcat file1 file2 >> filetoappendto.txt??Rm -rf dir1 | tee error log

Ans: Fault handlers are also an interrupt handler with an exception that the interrupt handlers cannot sleep. Fault handlers sleep in the context of the process that caused the memory fault. The fault refers to the running process and no arbitrary processes are put to sleep.

Ans: Splitting is done by a system call named fork. Proc_id = fork (); splits the program into two copies, both of which continue to run. The only difference between the two is the value returned by fork, the process-id. Two copies of the program are made by the fork. In the child, the value returned by fork is zero, so it calls execlp, which does the command line and then dies. In the parent, fork returns non-zero so it skips the execlp.

Ans:  When you execute a program on your UNIX system, the system creates a special environment for that program. This environment contains everything needed for the system to run the program as if no other program were running on the system. Each process has process context, which is everything that is unique about the state of the program you are currently running. Every time you execute a program the UNIX system does a fork, which performs a series of operations to create a process context and then execute your program in that context. The steps include the following:
Allocate a slot in the process table, a list of currently running programs kept by UNIX.
Assign a unique process identifier (PID) to the process.
iCopy the context of the parent, the process that requested the spawning of the new process.
Return the new PID to the parent process. This enables the parent process to examine or control the process directly. After the fork is complete, UNIX runs your program.

Ans: When it is started by the shell, a program inherits three open files, with file descriptor 0, 1 and 2 called the standard i/p, the standard o/p, and the standard error. If the program reads’0’ and writes descriptors 1 and 2, it can do I/O without opening files.

Ans: Grep is a pattern search command. It searches for the pattern, specified in the command line with appropriate option, in a file(s).
Syntax: grep
Example: grep 99mx mcafile

Ans: Zombie process: They do not take any up physical memory.
Processes locked in memories that are updating the region of the process.
Kernel swaps only the sleeping processes rather than the ?ready-to-run? Processes, as they have the higher probability of being scheduled than the Sleeping processes.

Ans: A Region is a continuous area of a process’s address space (such as text, data and stack). The kernel in a? Region Table? That is local to the process maintains region. Regions are sharable among the process.

Ans: Memory architecture must based on Pages. The machine must support the? Restartable? Instructions.

Ans: You have to specify the screen size each time you use P. $P-36.
Also you could put a shell file in your bin.
$cat/usr/you/bin/p
Exec/usr/bin/p-36$*
$
Another solution is to modify p to use an environment variable that defines the properties of your terminal.