There are a few things you should try out in order to be ready for the rest of the homeworks. Note that you're not expected to know this immediately; I and the TAs will be covering this material over the first two weeks.

1. Ensure you have a CUNIX account. It's preferable (although not absolutely required) that you have an "extended instructional" account, as it has fewer limitations as to what you can do on CUNIX. See http://www.columbia.edu/acis/accounts/Student_Accounts.html for more details.
2. Make sure you can log onto cunix.cc.columbia.edu; this is the Columbia UNIX computing cluster capable of running the latest version of Java. Note that you should not telnet to cunix; you should use a secure telnet-like protocol called ssh (AcIS is planning to turn off telnet this semester). If you want the ability to ssh from a Windows box at home, use a free tool like Teraterm Pro (http://www.columbia.edu/acis/software/teraterm/).
3. Download, and compile a test "hello world" program in your respective language. To do this, get hello.c or HelloWorld.java, put them into your CUNIX account, and either type:
   • For C, gcc hello.c (and then run ./a.out to run the compiled program);
   • For Java, javac HelloWorld.java (and then run java HelloWorld to run the compiled program).

That's it! Once you've done the above, you're ready to develop on the CUNIX cluster. While you do not have to (i.e., you can use a Windows IDE), you will be expected to test your code on cunix, as we will be grading it there. If you have problems, talk to a TA during the first lab (which will be in the second week of the semester). The first few weeks are a perfect opportunity to meet them and make sure you're off the ground and running, as you won't have time later in the semester to debug account and C/Java issues.