CSI 3131 Lab 1 Observing Process Behaviour Running

CSI 3131 – Lab 1 Observing Process Behaviour

Running Linux under Virtual PC § Start Virtual PC § § This Windows program provides a virtual machine to run any other operating system It offers an environment that looks like the raw computer system, that is, the hardware. § Select Site. Dev Machine and click Start § This will have Virtual PC start up a virtual machine and boot the Linux OS named Site. Dev § Log in with the user “test 1” and password “site” § § The same password can be used to log in as root – this is the administrator account. It is always safer to work with a regular account to prevent damaging important system files. § Use this account to complete the lab.

Linux Processes § Linux presents information on processes via the file system § § § Statistics on running processes can be examined by opening regular files. Please note that these files do not exist on the hard drive, but in main memory. In fact they are not files at all, but simply system data presented as files. The directory /proc contains a set of directories and files that provides • • § Each process has a unique identifier, called the PID (Process IDentifier). In /proc, the PID is presented as a directory. • § access to general OS information and information about each process running on the system. The contents of the PID directory provides information on the corresponding process. You can obtain documentation on the proc directory using “man proc” command

Objective of the lab § In the first part of the lab, you shall examine how a process executes and changes § § Some utilities (shell programs) and C programs have been provided to examine the changes in processes (by reading the contents of the /proc directory) as they execute different programs. You will gain insight into the state of a process and the difference between running in the two modes of execution (kernel and user). § In the second part of the lab, you shall gain experience with your first system calls – fork, exec, and kill § § These system calls provide the means to create new processes to run programs (fork and exec) and to terminate processes (using kill). Note that these are the same system calls used by the SHELL (your CLI interface) to manipulate processes

§ You have this week and next week to complete the lab, so take your time to understand what you are doing. § § Follow the instructions in the lab writeup. The TA shall circulate in the room to help answer any questions § Good luck.