- Is used for variable assignment
- Duplicates the input stream to the output stream
- Is used to output text to the console*
- Tests a variable for duplication
- Copies variables from one to another
- A file begins with
#!/bin/csh. This means:
- Nothing, this is a comment
- C Shell compatibility mode is enabled
- The operator should not be using /bin/csh
- Running the script will invoke /bin/csh to interpret the rest of the file*
- This is a Perl script
- Which are appropriate editors for writing shell scripts? (choose two)
- LibreOffice Writer
- Most of nano’s commands take the form of:
- Control and another character*
- Alt and another character
- Mouse clicks
- The F1 through F12 function keys
- Escape followed by another character
- What does this shell script do?
if [ ! –d $FOO ]; then
- Creates /tmp/foo if it does not exist*
- Makes the /tmp/foo directory if a file by that name exists
- Outputs a message to the screen
- Creates /tmp/foo and raises an error if there is a problem
- Nothing, since there is a problem with the conditions in the if statement
- Which of the following are correct about for and while loops? (choose two)
- for loops operate over a fixed list of items*
- while loops operate over a fix list of items
- for loops have a test each cycle to determine if it should run again
- while loops have a test each cycle to determine if it should run again*
- for loops require a variable over which to iterate
- Given the following part of a script:
if [ -f $1 ]; then
echo “I am here”
What is the meaning of $1?
- It is a special variable that indicates the exit code of the command before it
- It is the first argument passed to the script*
- It is a file called $1
- It is a parameter to –f, indicating the size of the file
- It is a list of files that gets interpolated
- Given the following script that is run through
./test.sh hello goodbye:
if [ -f $2 ]; then
echo “I am here”
- When will “I am here” be printed?
- If there are two files in the current directory
- The script will always print “I am here”
- If a file called “hello” exists in the current directory
- If a file called “goodbye” exists in the current directory*
- What is the correct way to assign the word “Hello” to a variable?
- echo “Hello” > A
- A=”Hello” *
- echo $A “Hello”
- A = “Hello”
- What is the correct way to save the current directory to a variable?
- A=`pwd` *
- pwd $A
- pwd | $A
- Which shell command accepts input from the user’s keyboard?
- What information is held inside $? ?
- The current process id
- The number of arguments passed to the script
- The current user ID
- The previous command’s exit code*
- The name of the command run
- How would you finish your script with an exit code of 42?
- return 42
- exit 42*
- break 42
ifcommand looks for what exit code to consider a condition to be true?
- 0 *
- The number of users logged in is in a variable called USERS. How would you test to see if 5 users are logged in?
- test –f USERS=5
- test $USERS = 5
- test $USERS,5
- test $USERS –eq 5 *
- test $USERS –a 5
- Given the following script:
while [ ! –f /tmp/foo ]; do
echo –n “.”
process_data > /tmp/foo
Which of the following are true? (choose two)
- If a file called /tmp/foo exists, process_data won’t be run*
- The screen will fill with dots.
- /tmp/foo will be removed if it exists
- process_data will never be run
- process_data will be called at most once*
- A conditional that lets you make multiple comparisons with a pattern is called:
- What is the meaning of
$(( $i + 1))?
- 1 will be added to the i variable*
- This will return the value of the next argument to the script
- This runs the command stored in variable i
- If i is 0, the loop will stop
- This will return the value of the first argument to the script
- How would you write a test that says “if /tmp/foo is a directory or USERS is greater than 5”?
- test –d /tmp/foo | $USERS > 5
- test –f /tmp/foo –o $USERS –ge 5
- test –d /tmp/foo –o $USERS –gt 5 *
- test /tmp/foo || $USERS > 5
- test /tmp/foo –d –o $USERS -gt 5
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