15-213 Intro to Computer Systems: Frequently Asked Questions
- Where do I find telnet on the shark machines?
- Does my proxy need to support POST requests?
- No, it only needs to support GET requests.
- Why does my proxy seem unable to properly handle images or other non-text content?
- Certain functions are designed to deal specifically with text; as such, they make certain assumptions about the data on which they operate, and their termination conditions in particular may be inappropriate for non-text content. Be wary of how you use that class of functions when implementing your proxy server.
Why are warnings like "unused parameter" being reported as errors?
- On some labs we have set flags (-Wall -Wextra) for the compiler to generate
more warnings than usual. We also set a flag (-Werror) to treat warnings as
- Any class of errors that can be detected by the compiler should be addressed
sooner rather than later.
Why am I geting an error: implicit declaration of function 'getopt'?
General Programming Issues
When I try to run an executable file included in a lab handout, I get a "Permission denied" error. What should I do?
- The executable bit is not set. Run "chmod +x <filename>" to set the executable bit.
- This problem may occur if you extract the handout tarball on a Windows machine. Always extract the handout on a Linux machine.
How do I extract a tarball on a Linux machine?
- Run "tar -xvf <filename>" to extract it.
General Course Issues
Why can't I access Autolab?
- Did you recently join the course? It is possible you do not yet have an account.
- Email the staff list if you need an account created for you.
Why can't I access the shark machines?
- You should be able to access the shark machines with your Andrew credentials. Email the staff list if you have trouble.
Must I work on the shark machines?
- Your work will be graded on the shark machines, so it is in your best interest to work there.
- For most labs, you may alternatively work on the Andrew Unix machines, which are nearly identical.
- You must complete bomblab and buflab on a shark machine.
Should I read the lab writeup before seeking help?
- Did we say, "Yes"?
- Yes, we did.
- Please read the lab writeups.
How can I get help?
- Email us at firstname.lastname@example.org.
- Stop by during office hours.
- Schedule a 1:1 meeting with your instructors or TAs.
Must I attend a particular recitation?
- You may attend any recitation you wish as long as the instructor leading the recitation allows it.
- Please make sure the recitation you normally attend is the one specified on your Autolab account; if this is not the case, email the staff list.
I have some command line output that I'd like to send to the staff. Should I send it as a screenshot?
- No. Text (copy and paste) is fine.
My editor shows me that my c code looks fine, but when my TA prints it out it looks different!