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→INVESTIGATION 2: MANAGING PROCESSES
# Issue a Linux command to confirm that you are located in your '''home''' directory.<br><br>The '''sleep''' command '''pauses for a specified number of seconds''' before returning to the shell prompt.<br>In the tutorial, we will be using this command to '''simulate''' the management of "long-running" processes.<br><br>
# Issue the following Linux command: <span style="color:blue;font-family:courier;font-weight:bold">sleep 700</span><br><br>Notice that this process will run for '''700 seconds''', and is forcing the user to '''wait''' until this process finishes.<br>A process that is '''running in the terminal''' is referred to as a '''foreground processes'''.<br><br>The Unix/Linux system is designed to allow users to send '''preemptive signals''' to manage those processes.<br><br>
# Press the following '''key combination''' to '''terminate''' the command running on the terminal: <span style="color:blue;font-family:courier;font-weight:bold">ctrl-c</span><br><br>You should notice that the process that was running in the foreground has been '''interrupted''' (i.e. terminated).<br>'''NOTE:''' The '''ctrl-c''' key combination sends '''SIGINT''' ('''Signal Interrupt''' - which is signal '''#2''') signal to<br>to ''terminate'' a process that is running on the terminal (i.e. the '''foreground''').<br><br>
# Reissue the Linux command: <span style="color:blue;font-family:courier;font-weight:bold">sleep 700</span><br><br>
# Press the '''key combination''': <span style="color:blue;font-family:courier;font-weight:bold">ctrl-z</span><br><br>[[Image:process-jobs1.png|thumb|right|300px|Running a command in the terminal, pressing '''ctrl-z''' to place into the background, and issuing the '''jobs''' command to view processes in the background.]]
