Diomidis D. Spinellis Frequently Asked Questions

Contents of this Page

• Miscellaneous
• Greek Character Encoding
• Obfuscated C

Separate Dedicated Pages

• Code Reading Book
• Code Quality Book
• UMLGraph (software)
• CScout (software)
• ckjm (software)
• Academic Matters (in Greek)

Miscellaneous

1. You have not answered my email [...]
   First of all note that emails requiring action from me can remain up to a month in my inbox. Due to the huge number of spam virus messages I am receiving I have implemented a very aggressive email filtering policy based on spamassassin. I also manually delete suspicious email messages without a second thought. An email titled "Urgent assistance required" or containing an executable program, is guaranteed to get trashed. Finally, I seldom answer email messages that do not require an answer, or are answered in this FAQ list. Based on the above, consider resending me your email, if you think you should have gotten a reply.

2. Can you please post/email me your paper titled [...]?
   Please download it from my publications page. If it is not there, I do not have it.

3. I sent you a Facebook friend request and you seem to have ignored it. Why?
   I use Facebook to keep track of the names and faces of the people I know. If your Facebook profile doesn't include your real name or a recognizable face, or if I don't know you (even through email), I will ignore the request. Also note that when I'm busy I acknowledge friend requests in batches so it can take up to a week to process your request.

4. What is the latest version of your [...] program? Where can I find it?
   Look in my public software page. If it's not there, I don't have it or it's not fit for release; sorry.

5. I need to write a program to add hexadecimal integers / do heapsort / calculate factorial / solve the n-queens problem. Can you please help me?
   Sorry, I do not do classwork assignments. In addition, the idea of assignments is to do them on your own.

6. Hello,
   I'm a Science Computing student at [...], and would like to keep contact with you and the others authors of the article XYZ That is because we are make a reserch over XYZ. We are looking for some comments, scientific articles and some other stuff on that subject. We also have some questions about the mentioned article .
   Thanks for your atention,
   Read the answer to the previous question.

7. I'm looking for documentation on how to check the validity of credit card numbers.
   Read the international standard ISO/IEC 781:1989 (I do not know where you can find it; contact ISO.) Alternatively download the "Credit Card Checksum" function from my public software page.

8. Can I use your trace program to trace Windows applications?
   Trace is a 16 bit MS-DOS application and can not be used to trace Windows programs.

Contents Home

Greek Character Encoding

1. Where can I find information on Greek character font encoding?
   Have a look at RFC-1947 and at this table.

2. In RFC-1947 you refer to 'M7' as being character set 8859-7 as implemented in Microsoft Windows 3.1, 3.11 or 95. How does this differ, if at all, to Windows CP1253?
   RFC-1947 M7 is Windows CP1253. At the time the RFC was written I was not aware of that code page designation.

3. Where can I find Greek fonts and keyboard drivers?
   Try the Hellenic Resources Institute.

4. Where can I obtain Greek standard documents (keyboard layout, transcription, transliteration, encodings, etc.)?
   From the Greek Standards Organisation (ELOT). Their address is:
   Axarnon 313
   GR-111 35 Athens
   GREECE

5. I have a problem reading / viewing / loading / converting / writing / processing Greek files on my computer. Can you please help me?
   I am very sorry, but I really have not got time to answer to such questions. Try consulting a local expert, a friend, or your computer or operating system vendor. You could also try to convert the files into a format you can process using my grconv Greek code converter.

Contents Home

Obfuscated C

1. I found your obfuscated C code contest program [name of winning program]. Is there an unobfuscated version of it? Can you please explain me how it works?
   The #include "/dev/tty" program (1988 best abuse of the rules winner) runs whatever C code you type at the (Unix) terminal at compile time.

   The Basic interpeter (1990 Best Language Tool winner) and the Basic compiler (1991 Most Well Rounded winner) programs are analysed in:
   Don Libes. Obfuscated C and Other Mysteries. John Wiley and Sons, 1993.

   The 1995 Abusing The Rules winner program [ab]uses the contest rules that allowed a generous amount of whitespace for improving the entries' format by encoding text as whitespace

2. Can I use your Basic compiler program to convert Basic programs into C?
   The compiler only works for a small subset of Basic and produces quite inefficient code. I do not recommend it.

3. Can I use your Basic interpreter program to run Basic programs?
   The interpreter only works for a very small subset of Basic and its runtime efficiency is abysmal (the interpreter is actually implemented as a custom virtual machine executed by a VM interpreter written in C).

   There are at least two free Basic interpreters that may suit your purpose: yabasic and bwbasic. The former is a plain Basic interpreter, or really p-code compiler + interpreter, like Perl. The latter provides a classic Basic "IDE", with line-number-based editing and all; unrecognized commands are executed by the shell, immediately or as part of the program. oth are available under the GPL for Microsoft Windows and Unix systems. (Contributed by John Cowan).

4. Where is the Obfuscated C Code Contest home page?
   http://www.ioccc.org/index.html

5. Did you ever do any additional work on the DDS-BASIC interpreter/compiler?
   No, I consider IOCCC submissions a form of art. They are not to be "improved".

Unless otherwise expressly stated, all original material on this page created by Diomidis Spinellis is licensed under a Creative Commons Attribution-Share Alike 3.0 Greece License.
Last modified: $Date: 2010/12/03 12:47:05 $