Assignment 2, due Sept. 9
On all assignments, your name must be legible as it appears on your University ID card! Assignments are due at the start of class on the day indicated (usually Friday). Exceptions will be by advance arrangement unless there is what lawyers call "an act of God" (something outside your control). Homework must be turned in on paper, either in class or in the teaching assistant's mailbox. Never push late work under someone's door!
a) Virtualization began with virtual memory. In what decade did virtual memory emerge? What was the first system to offer virtual memory? (0.5 points)
The Ferranti Atlas, which came to market in the early 1960s. The Burroughs 5000 is an alternate answer, coming out at about the same time.
b) The second step in virtualization was the virtual machine operating system. In what decade was the first virtual machine operating system released (0.5 points)
The IBM CP/CMS operating system on the 360/67 emerged in the 1960s as a research system. It was commercialized as VM/370 in the early 1970s.
The experiment produces the following output, indicating tcsh.echo $SHELL /bin/tcsh
#!/bin/tcsh echo X $argv $argv $argv
a) What is the output if you type this shell command? (0.5 points)
./script echo hello world
The output is:X echo hello world hello world hello world
b) What is the output if you type this shell command? (0.5 points)
./script ./script ./script ./script
The output is:X ./script ./script ./script X ./script ./script X ./script X X X ./script X X X ./script ./script X ./script X X X ./script X X
c) What terminates the recursion? (0.5 points)
With each recursive call, the parameter list is shifted one place left. Eventually, it is shifted away to be blank, causing termination.