Question 1: Create a user named testuser using sudo to run the adduser command. Log in as that user, su will do the trick. Create a file DONOTTOUCH which is writeable only by testuser.
Prepare an executable CHANGETHATFILE that modifies DONOTTOUCH which is read and perform for 'others' and, in addition, has a setuid bit such that other users who execute that program can run as testuser to modify DONOTTOUCH. Script your show and any code you have written.
Question 2: What does the 'execute' bit mean for a directory? Show how the execute bit works for referencing files within directories. Does the execute bit need to be set for ANY directory on the path to a file you wish to reference?
Show and script evidence for the answers to the given questions - What does the 'execute' bit mean for a directory?