What will be in out.txt? ls nonexistentfile | grep "No such file" > out.txt

What will be the difference between the output on the screen and the contents of out.txt mysql < file.sql > out.txt

How would you find the last copy command run in your history?

In order to write a script that iterates through the files in a directory, which of the following could you use?

When executing a command and passing the output of that command to another command, which character allows you to chain these commands together?

Which statement checks whether the variable num is greater than five?

What file would match the code below? ls Hello[[.vertical-line.]]World

Which file allows you to save modifications to the shell environment across sessions?

What is the difference between the $@ and $* variables?

How can you gather history together for multiple terminals?

Which variable would you check to verify that the last command executed successfully?