9th International Obfuscated C Code Contest Guidelines, Hints and Comments Copyright (c) 1992, Landon Curt Noll & Larry Bassel. All Rights Reserved. Permission for personal, educational or non-profit use is granted provided this this copyright and notice are included in its entirety and remains unaltered. All other uses must receive prior permission in writing from both Landon Curt Noll and Larry Bassel. ABOUT THIS FILE: This file is intended to help people who wish to submit entries to the International Obfuscated C Code Contest (IOCCC for short). This is not the IOCCC rules, though it does contain comments about them. The guidelines should be viewed as hints and suggestions. Entries that violate the guidelines but remain within the rules are allowed. Even so, you are safer if you remain within the guidelines. You should read the current IOCCC rules, prior to submitting entries. The rules are typically sent out with these guidelines. WHAT IS NEW IN 1992: The size rules are different this year. There is a more relaxed rule to encourage formatting styles beyond rectangular blobs of C code. The build file (how to compile) has been expanded as well. See the rules, and OUR LIKES AND DISLIKES for details. The entry format is better (for us anyway). The program mkentry.c provides a convenient way to form an entry. See ENTRY FORMAT. The original entry source, build and resulting binary should be treated as read-only. There is a provision to allow entries to modify these files indirectly. See ENTRY FORMAT. This year, we are experimenting with a new category of programs: X clients. X client entries should be as portable as possible. See OUR LIKES AND DISLIKES. HINTS AND SUGGESTIONS: You are encouraged to examine the winners of previous contests. See FOR MORE INFORMATION for details on how to get previous winners. Keep in mind that rules change from year to year, so some winning entries may not be valid entries this year. What was unique and novel one year might be 'old' the next year. An entry is usually examined in a number of ways. We typically apply a number of tests to an entry: * look at the original source * If it is ANSI, convert tri-graphs to ASCII * C pre-process the source ignoring '#include' lines * C pre-process the source ignoring '#define' and '#include' lines * run it through a C beautifier * examine the algorithm * lint it * compile it * execute it You should consider how your entry looks in each of the above tests. You should ask yourself if your entry remains obscure after it has been 'cleaned up' by the C pre-processor and a C beautifier. Your entry need not do well under all, or in most tests. In certain cases, a test is not important. Entries that compete for the 'strangest/most creative source layout' need not do as well as others in terms of their algorithm. On the other hand, given two such entries, we are more inclined to pick the entry that does something interesting when you run it. We try to avoid limiting creativity in our rules. As such, we leave the contest open for creative rule interpretation. As in real life programming, interpreting a requirements document or a customer request is important. For this reason, we often award 'worst abuse of the rules' to an entry that illustrates this point in an ironic way. If you do plan to abuse the rules, we suggest that you let us know in the remarks section. Please note that an invitation to abuse is not an invitation to break. We are strict when it comes to the 3217 byte size limit. Also, abusing the entry format tends to annoy more than amuse. We do realize that there are holes in the rules, and invite entries to attempt to exploit them. We will award 'worst abuse of the rules' and then plug the hole next year. Even so, we will attempt to use the smallest plug needed, if not smaller. :-) Check out your program and be sure that it works. We sometimes make the effort to debug an entry that has a slight problem, particularly in or near the final round. On the other hand, we have seen some of the best entries fall down because they didn't work. We tend to look down on a prime number printer, that claims that 16 is a prime number. If you do have a bug, you are better off documenting it. Noting "this entry sometimes prints the 4th power of a prime by mistake" would save the above entry. And sometimes, a strange bug/feature can even help the entry! Of course, a correctly working entry is best. OUR LIKES AND DISLIKES: Doing masses of #defines to obscure the source has become 'old'. We tend to 'see thru' masses of #defines due to our pre-processor tests that we apply. Simply abusing #defines or -Dfoo=bar won't go as far as a program that is more well rounded in confusion. Many ANSI C compilers dislike the following code, and so do we: #define d define #d foo <-- don't expect this to turn into #define foo int i; j; <-- don't use such implicit type declarations int k; We suggest that you use ANSI C compilers if possible. If you must use non-ANSI C, such as K&R C, try to avoid areas that give ANSI C compilers problems. Small programs are best when they are short, obscure and concise. While such programs are not as complex as other winners, they do serve a useful purpose. They are often the only program that people attempt to completely understand. For this reason, we look for programs that are compact, and are instructional. One line programs should be short one line programs, say around 80 bytes long. Getting close to 160 bytes is a bit too long for one liners in our books. We tend to dislike programs that: * are very hardware specific * are very OS or Un*x version specific (index/strchr differences are ok, but socket/streams specific code is likely not to be) * dump core or have compiler warnings (it is ok only if you warn us in the 'remark' header item) * won't compile under both BSD or SYS V Un*x * abusing the build file to get around the size limit * obfuscate by excessive use of ANSI tri-graphs * are longer than they need to be * are similar to previous winners * are identical to previous losers :-) Unless you are cramped for space, or unless you are entering the 'best one liner' category, we suggest that you format your program in a more creative way than simply forming excessively long lines. The build file should not be used to try and get around the size limit. It is one thing to make use of a several -D's to help out, but it is quite another to use 200+ bytes of -D's in order to try and squeeze the source under the size limit. You should feel free to make use of the build file space, but you are better off if you show some amount of restraint. We allowed whitespace, and in certain cases ; { or } do not impact your program size (up to a certain point), because we want to get away from source that is simply a compact blob of characters. Given two versions of the same program, one that is a compact blob of code, and the other that is formatted more like a typical C program, we tend to favor the second version. Of course, a third version of the same program that is formatted in an interesting and/or obfuscated way, would definitely win over the first two! We suggest that you avoid trying for the 'smallest self-replicating' program. We are amazed at the many different sizes that claim to be the smallest. There is nothing wrong with self-replicating programs. In fact, a number of winners have been self-replicating. You might want to avoid the claim of 'smallest', lest we (or others) know of a smaller one! X client entries should be as portable as possible. Entries that adapt to a wide collection of environments will be favored. Don't depend on a particular type of display. For example, don't depend on color or a given size. Don't require backing store. X client entries should avoid using X related libraries and software that is not in wide spread use. We ask that such X client entries restrict themselves to only the low level Xlib and the Athena widget set (libX11.a, libXaw.a, libXmu.a and libXt.a). Don't use M*tif, Xv*ew, or OpenL*ok toolkits, since not everyone has them. Avoid depending on a particular window manager. Not everyone has X11r5, and some people are stuck back in X11r3 (or earlier), so try to target X11r4 without requiring X11r4. Better yet, try to make your entry run on all version 11 X Window Systems. X client entries should not to depend on particular items on .Xdefaults. If you must do so, be sure to note the required lines in the ---remark--- section. Better yet, give an xrdb -merge command as part of the build. We like programs that: * are as concise and small as they need to be * do something at least quasi-interesting * pass lint without complaint (not a requirement, but it is nice) * are portable * are unique or novel in their obfuscation style * MAKE USE OF A NUMBER OF DIFFERENT TYPES OF OBFUSCATION * make us laugh and/or throw up :-) Some types of programs can't excel in some areas. Of course, your program doesn't have to excel in all areas, but doing well in several areas really does help. We freely admit that interesting, creative or humorous comments in the ---remark--- section helps your chance of winning. If you had to read of many twisted entries, you too would enjoy a good laugh or two. We think the readers of the contest winners do as well. Be creative! ENTRY FORMAT: In order to help us process the many entries, we must request your assistance by formatting your entries in a certain way. This format, in addition, allows us to quickly separate information about the author from the program itself. (see JUDGING PROCESS) We have provided the program, mkentry, as an example of how to format entries. You should be aware of the following warning that is found in mkentry.c: This program attempts to implement the IOCCC rules. Every attempt has been made to make sure that this program produces an entry that conforms to the contest rules. In all cases, where this program differs from the contest rules, the contest rules will be used. Be sure to check with the contest rules before submitting an entry. You are not required to use mkentry. It is convenient, however, as it attempts to uuencode the needed files, and attempt to check the entry against the size rules. If you have any suggestions, comments, fixes or complaints about the mkentry.c program, please send Email to the judges. (see below) The following is a sample entry: ---entry--- rule: 1992 title: chonglab entry: 0 date: Mon Feb 17 13:58:57 1992 host: Un*x v6, pdp11/45 2.9BSD, pdp11/70 ---remark--- This is a non-obfuscated obfuscated C program. It is likely not to win a prize. But what do you expect from a short example! (yes, Hello world progs have become old too) ---author--- name: Landon Curt Noll org: IOCCC Judging Group addr: Toad Hall San Francisco, CA 94101 USA email: chongo@toad.com anon: n ---author--- name: Larry Bassel org: IOCCC Judging Group addr: Toad Hall San Francisco, CA 94101 USA email: hoptoad!sun!lab lab@sun.com anon: n ---info--- begin 444 info.file M2&$A("!792!G;W0@>6]U('1O(&QO;VLA"@I4:&%T('1H870@:7,L(&ES+@I4 M:&%T('1H870@:7,@;F]T+`H@("`@:7,@;F]T('1H870@=&AA="!N;W0@:7,N M"E1H870@:7,L('1H870@=&AA="!IW!R:6YT9B@B2&5L;&\L('=O special_build sh < special_build * Assume that we will use the entry title. Send us a version of your build/program files that uses the name convention. You should uuencode these files in ---data--- sections. If your entry needs to modify its source, info or binary files, please say so in the ---remark--- section. You should try to avoid touching your original build, source and binary files. You should arrange to make copies of the files you intend to modify. This will allow people to re-generate your entry from scratch. Remember that your entry may be built without a build file. We typically incorporate the build lines into a Makefile. If the build file must exist, say so in the ---remark--- section. If your entry needs special info files, you should uuencode them into ---info--- sections. In the case of multiple info files, use multiple ---info--- sections. If no info files are needed, then skip the ---info--- section. Info files are intended to be input, or detailed information that does not fit well into the ---remark--- section. For example, an entry that implements a compiler might want to provide some sample programs for the user to compile. An entry might want to include a lengthly design document, that might not be appropriate for a 'hints' file. Info files should be used only to supplement your entry. For example, info files may provide sample input or detailed information about your entry. Because they are supplemental, the entry should not require them exist. In some cases, your info files might be renamed to avoid name conflicts. If info files should not be renamed for some reason, say so in the ---remark--- section. Info files must uudecode into the current directory. If they absolutely must be renamed, or moved into a sub-directory, say so in the ---remark--- section. JUDGING PROCESS: Entries are judged by Larry Bassel and Landon Curt Noll. Entries are unpacked into individual directories. The Email message is unpacked into individual files, each containing: ---entry--- section all ---author--- sections all ---info--- sections ---build--- section ---program--- section any other text, including the Email message headers Prior to judging, the 'any other text' file is scanned to be sure it does not contain useful information (or in case the entry was malformed and did not unpack correctly). Information from the ---author--- sections are not read until the judging process is complete, and then only from entries that have won an award. The above process helps keep us biased for/against any one particular individual. We are usually kept in the dark as much as you are until the final awards are given. We like the surprise of finding out in the end, who won and where they were from. We attempt to keep all entries anonymous, unless they win an award. Because the main 'prize' of winning is being announced, we make all attempts to send non-winners into oblivion. We remove all non-winning files, and shred all related paper. By tradition, we do not even reveal the number of entries that we received. (for the curious, we do indicate the volume of paper consumed when presenting the IOCCC winners at talks) After the Usenix announcement, we attempt to send Email to the authors of the winning entries. One reason we do this is to give the authors a chance to comment on the way we have presented their entry. They are given the chance to correct mistakes, typos. We often accept their suggestions/comments about our remarks as well. This is done prior to posting the winners to the wide world. Judging consists of a number of elimination rounds. During a round, the collection of entries are divided into two roughly equal piles; the pile that advances on to the next round, and the pile that does not. We also re-examine the entries that were eliminated in the previous round. Thus, an entry gets at least two readings. A reading consists of a number of actions: * reading the ---entry--- section * reading the uudecoded ---build--- section * reading the uudecoded ---program--- section * reading the uudecoded ---info--- section(s), if any * passing the source thru the C pre-processor shipping over any #include files * performing a number of C beautify/cleanup edits on the source * passing the beautified source thru the C pre-processor shipping over any #include files In later rounds, other actions are performed: * linting the source * compiling/building the source * running the program * performing misc tests on the source and binary Until we reduce the stack of entries down to about 25 entries, entries are judged on an individual basis. An entry is set aside because it does not, in our opinion, meet the standard established by the round. When the number of entries thins to about 25 entries, we begin to form award categories. Entries begin to compete with each other for awards. An entry often will compete in several categories. The actual award category list will vary depending on the types of entries we receive. A typical category list might be: * best small one line program * best small program * strangest/most creative source layout * most useful obfuscated program * best game that is obfuscated * most creatively obfuscated program * most deceptive C code * best X client (see OUR LIKES AND DISLIKES) * best abuse of ANSI C * worst abuse of the rules * We do not limit ourselves to this list. For example, a few entries are so good/bad that they are declared winners at the start of the final round. We will invent awards categories for them, if necessary. In the final round process, we perform the difficult tasks of reducing the remaining entries (typically about 25) down to 8 or 10 winners. Often we are confident that the entries that make it into the final round are definitely better than the ones that do not make it. The selection of the winners out of the final round, is less clear cut. Sometimes a final round entry good enough to win, but is beat out by a similar, but slightly better entry. For this reason, it is sometimes worthwhile to re-enter an entry that failed to win on a previous year. There have been winners that lost in a previous year. Of course, in those cases, improving on the entry made the difference! More often that not, we select a small entry (usually one line), a strange/creative layout entry, and an entry that abuses the contest rules in some way. In the end, we traditionally pick one entry as 'best'. Sometimes such an entry simply far exceeds any of the other entry. More often, the 'best' is picked because it does well in a number of categories. ANNOUNCEMENT OF WINNERS: The first announcement, occurs at a Summer Usenix conference. By tradition, this is done during the latter part of the UUNET/IOCCC BOF. Winning entries will be posted in late July/Aug to the following groups: comp.lang.c comp.unix.wizards alt.sources In addition, pointers to these postings are posted to the following comp.sources.d alt.sources.d misc.misc comp.sources.misc Winning entries will be deposited into the uunet archives. See below for details. Often, winning entries are published in magazines such as "The C Users Journal". Winners have appeared in books ("The New Hackers Dictionary") and on various T-Shirts. Last, but not least, winners receive international fame and flames! :-) FOR MORE INFORMATION: You may contact the judges by sending Email to the following address: ...!{apple,pyramid,sun,uunet}!hoptoad!judges (not the address for judges@toad.com submitting entries) Questions and comments about the contest are welcome. One may obtain a copy of the current rules, guidelines or mkentry program may be obtained from the judges using the Email address above. Please use the following subject when Emailing your request: send rules One may also obtain the above items, we well as winners of previous contests, via anonymous ftp from: host: ftp.uu.net (137.39.1.9) user: anonymous pass: yourname@yourhost dir: pub/ioccc Often, contest rules, guidelines and winners are available from archive sites. Check comp.sources.unix archives, for example. You may also request previous winners by Email, using the judges Email address, though we ask that you do this as a last resort. If you must request winners via Email, use the following subjects: send all winners (to obtain winners all previous winners) send year winners (to obtain winners for a given year, where year is one of 1984, 1985, 1986, ...) chongo /\cc/\ hoptoad!chongo Larry Bassel {uunet,ucbvax,cbosgd}|sun!lab