From 8a95f0c6bb2d6f168aa3b74b154919b9b731151d Mon Sep 17 00:00:00 2001 From: Landon Curt Noll Date: Mon, 1 Dec 2025 19:53:23 -0800 Subject: [PATCH] improve PR #246 - part 1 Fixed links between rules and guidelines. Add guideline about "Rule 2 - Size restrictions" not changing soon. Expand "Guidelines for Rule 13 - No carriage returns in prog.c". Put the word, "restrictions" into "Rule 2 - Size restrictions". While this is a **GOOD IDEA**, the concept needs to be rolled out over all of the rules, not just "Rule 2 - Size restrictions". Changed IOCCC Rules to version **29.13 2025-12-01**. Changed IOCCC Guidelines to version **29.06 2025-12-01**. Ran `make quick_www` to perform the above. --- faq.html | 15 +- faq.md | 19 +- next/guidelines.html | 462 ++++++++++++++++++++++++------------------- next/guidelines.md | 63 ++++-- next/rules.html | 28 +-- next/rules.md | 35 ++-- sitemap.xml | 14 +- 7 files changed, 369 insertions(+), 267 deletions(-) diff --git a/faq.html b/faq.html index a7cfce833..61b52293b 100644 --- a/faq.html +++ b/faq.html @@ -453,7 +453,7 @@

IOCCC FAQ Table of Contents

-

This is FAQ version 29.03 2025-11-30.

+

This is FAQ version 29.04 2025-12-01.

0. Entering the IOCCC: the bare minimum you need to know

+
+

Size rule slow to change

+
+

As you can read above, the Size rule is slow to change.

+

Given how long the IOCCC 2013-2020 size rule lasted, +one might expect the IOCCC 2024-date size rule to last +well into the 2030’s.

Jump to: top

Q 11.4: What is the Great Fork Merge?

diff --git a/faq.md b/faq.md index ec0fa6860..1f8e6a33f 100644 --- a/faq.md +++ b/faq.md @@ -1,6 +1,6 @@ # IOCCC FAQ Table of Contents -This is FAQ version **29.03 2025-11-30**. +This is FAQ version **29.04 2025-12-01**. ## 0. [Entering the IOCCC: the bare minimum you need to know](#enter_questions) @@ -40,7 +40,7 @@ This is FAQ version **29.03 2025-11-30**. - **Q 2.1**: How can I comment or make a suggestion on IOCCC rules, guidelines and tools? - **Q 2.2**: Are there any compiler warnings that I should not worry about in my submissions? - **Q 2.3**: What types of entries have been frequently submitted to the IOCCC? -- **Q 2.4**: How did an entry win the IOCCC that breaks Rule 2 - Size Limit? +- **Q 2.4**: How did an entry win the IOCCC that breaks Rule 2 - Size restrictions? - **Q 2.5**: How many submissions do the judges receive for a given IOCCC? - **Q 2.6**: How much time does it take to judge the contest? - **Q 2.7**: How many judging rounds do you have? @@ -144,7 +144,7 @@ This is FAQ version **29.03 2025-11-30**. - **Q 11.0**: How did the IOCCC get started? - **Q 11.1**: Why are some years missing IOCCC entries? - **Q 11.2**: What is the history of the IOCCC website? -- **Q 11.3**: How has the IOCCC size limit rule changed over the years? +- **Q 11.3**: How has the Rule 2 size restrictions rule changed over the years? - **Q 11.4**: What is the **Great Fork Merge**? - **Q 11.5**: What is an IOCCC BOF? - **Q 11.6**: I do not understand the IOCCC, can you explain it to me? @@ -8146,7 +8146,7 @@ Jump to: [top](#)
-### Q 11.3: How has the IOCCC size limit rule changed over the years? +### Q 11.3: How has the Rule 2 size restrictions rule changed over the years?
@@ -8221,6 +8221,17 @@ In later years, Rule 2 was split into two parts. These two parts of Rule 2 are: * Rule 2b: 2503 +
+#### Size rule slow to change +
+ +As you can read above, the Size rule is slow to change. + +Given how long the [IOCCC 2013-2020](#size_rule2013-2020) size rule lasted, +one might expect the [IOCCC 2024-date](#size_rule2024-xxxx) size rule to last +well into the 2030's. + + Jump to: [top](#) diff --git a/next/guidelines.html b/next/guidelines.html index f6bb03cc4..5e86a94ed 100644 --- a/next/guidelines.html +++ b/next/guidelines.html @@ -459,18 +459,18 @@ Copyright © 2025 Leonid A. Broukhis and Landon Curt Noll.

All Rights Reserved. Permission for personal, education or non-profit use is granted provided this copyright and notice are included in its entirety and remains unaltered. All other uses must receive prior permission in -writing by contacting the judges.

+writing by contacting the Judges.

Guidelines Version

-These IOCCC guidelines are version 29.05 2025-12-01. +These Guidelines are version 29.06 2025-12-01.

The | symbol indicates an change from the previous IOCCC.

-Because the IOCCC29 guidelines was a substantial rewrite, only important changes from IOCCC28 have been marked. +Because the IOCCC29 was a substantial rewrite, only important changes from IOCCC28 have been marked.

-

Be sure to read the IOCCC rules.

+

Be sure to read the Rules.

Guidelines for Rule 1 - C program

@@ -500,12 +500,13 @@ Some use of #include statements and/or implicit defines on the C co

As a guide, consider the level of #include statements and/or implicit defines on the C compiler command line that are found in -winning IOCCC entries, and try to NOT set a new record. +winning Entries, and try to NOT set a new record.

If you believe you need to significantly abuse #include statements and/or implicit defines on the C compiler command line, -then try to make a case for why in your submission’s remarks.md file: maybe the judges won’t reject your submission. +then try to make a case for why in your submission’s remarks.md file: maybe the Judges won’t reject your submission.

+

Jump to: top

@@ -525,7 +526,7 @@ You should pay attention to our observations on Rule 2 - Size restrictions, use the iocccentry(1) tool. For example:

    iocccsize prog.c
-

The IOCCC size tool algorithm can be summarized as follows:

+

The iocccsize(1) algorithm can be summarized as follows:

The size tool counts most C reserved words (keyword, secondary, and selected preprocessor keywords) as 1. The size tool counts all other bytes as 1 @@ -537,36 +538,39 @@ before the end of file.

counted by the IOCCC size tool.

In cases where the above summary and the algorithm implemented by -the IOCCC size tool iocccsize(1) conflict, the algorithm implemented -by the minimum required version of iocccsize(1) is preferred by the IOCCC -judges.

+iocccsize(1) conflict, the algorithm implemented +by the minimum required version of iocccsize(1) is preferred by the Judges.

Make sure iocccsize does not flag any issues with your prog.c.

-

NOTE: by default iocccsize will only report the rule 2b size, unless the +

NOTE: by default iocccsize will only report the size, unless the code surpasses the limit.

There a much less need to #define C reserved words in an effort to get around the size limits of Rule 2 - Size restrictions because of the iocccsize(1) algorithm.

Yes Virginia, the previous guideline sentence is an important hint!

+

Don’t expect the Rule 2 - Size restrictions to +change any time soon.

+

See the +FAQ on “How has the Rule 2 size restrictions rule changed over the years?”.

Jump to: top

-
+

If a group of people work on a submission, then they should register for the IOCCC -using either a group email address, or an email address for one of the authors. +using either a valid group email address, or an email address for one of the authors.

-Processing your registration is an activity overseen by an IOCCC judge. -Please be patient while an IOCCC judge processes your registration. +Processing your registration is an activity overseen by a Judge. +Please be patient while a Judge processes your registration.

It can take a few days to process your registration and for the server to email your details, therefore make sure to allow yourself ample time to register and submit your entries; DO NOT WAIT UNTIL THE FINAL DAYS -to register! The judges are NOT responsible for delayed or lost +to register! The Judges are NOT responsible for delayed or lost email or for those who wait until the last minute to try to register!

If after a few days you believe your registration hasn’t been process, then @@ -582,7 +586,7 @@ If you fail to change your temporary password by that deadline, then you’ll ne

See Entering the IOCCC: the bare minimum you need to know.

Jump to: top

-
+

Guidelines for Rule 7 - Original Work

@@ -608,74 +612,124 @@ In short: You created it, you own it, its an original work, or you have explicit FAQ on “May I use AI, LLM, Virtual coding assistants, or similar tools to write my submission?”.

Jump to: top

-
+
-

Do NOT register more than one account just try and get around the limit on the number of submission slots.

+

Do NOT register more than one account just to try and get around the limit on the number of submission slots.

+

Jump to: top

+ +

Don’t forget that the building of your program should be done +WITHOUT human intervention. So don’t do things such as:

+
    prog: prog.c
+        #echo this next line requires data from standard input
+        cat > prog.c
+        ${CC} prog.c -o prog
+

However, you can do something cute such as making your program +do something dumb (or cute) when it is built ‘automatically’, and +when it is run with a human involved, do something more clever. +For example, one could put in their Makefile:

+
    prog: prog.c
+        ${CC} prog.c -DNON_HUMAN_COMPILE -o prog
+        @echo "See remarks section about alternate ways to compile"
+

and then include special notes in your remarks.md file for +alternate / human intervention based building.

Jump to: top

+ -

We do realize that there are holes in the IOCCC rules, and invite +

+

We do realize that there are holes in the Rules, and invite submitters to attempt to apply creative rule interpretation. A rule abuse though, even if not rewarded, may result in a subsequent rule change for future contests.

We sometime award ‘Best abuse of the rules’ or ‘Worst abuse of the rules’, or some variation, to a submission that creatively attempts to exploit a holes in the -IOCCC rules.

-

When we do need to plug a hole in the IOCCC rules -or IOCCC guidelines, we will attempt to use a very small plug, +Rules.

+

When we do need to plug a hole in the Rules +or Guidelines, we will attempt to use a very small plug, if not smaller.

Or, maybe not. :-)

Legal rule abuse may involve, but is not limited to, doing things that are -technically allowed by the IOCCC rules and yet do not fit the spirit of what +technically allowed by the Rules and yet do not fit the spirit of what we intended to be submitted.

-

Legal abuse of the IOCCC rules is NOT an invitation to violate -the IOCCC rules (especially Rule 17 - +

Legal abuse of the Rules is NOT an invitation to violate +the Rules (especially Rule 17 - Use mkiocccentry). A submission that violates the -rules in the opinion of the IOCCC judges, +rules in the opinion of the Judges, WILL be disqualified. RULE ABUSE CARRIES A CERTAIN LEVEL OF RISK!

-

If you intend to abuse the IOCCC rules, +

If you intend to abuse the Rules, indicate so in your remarks.md file. You MUST try to justify, plead, beg, why you consider your rule abuse to be allowed under the -IOCCC rules. Humor or creativity help plead a case.

+Rules. Humor or creativity help plead a case.

As there is no guarantee that you will succeed, you might consider submitting an -alternate version that conforms to the IOCCC rules, if it might -otherwise be interesting; one that does not abuse the IOCCC rules +alternate version that conforms to the Rules, if it might +otherwise be interesting; one that does not abuse the Rules and one that does, making sure to note in the one that does not abuse the rules -that this is another version, so that the judges do not assume you uploaded it +that this is another version, so that the Judges do not assume you uploaded it by mistake.

If you do bypass the mkiocccentry(1) warnings about Rule 2a - Gross Size and/or about Rule 2b - Net Size or any other -rule and submit a submission anyway, you MUST try to justify why the IOCCC -IOCCC judges should not reject your submission due to a rule +rule and submit a submission anyway, you MUST try to justify why the +Judges should not reject your submission due to a rule violation, and you would be wise to do this towards the top of your remarks.md -file.

-

We are often asked why the contest IOCCC rules and IOCCC -guidelines seem strange or contain mistakes, flaws, or +file so as not to be overlooked.

+

We are often asked why the contest Rules and Guidelines seem strange or contain mistakes, flaws, or grammatical errors. One reason is that we sometimes make genuine mistakes, but in many cases such problems, flaws or areas of confusion are deliberate.

-

Changes to IOCCC rules and IOCCC guidelines in +

Changes to Rules and Guidelines in response to rule abuses, are done in a minimal fashion. Often we will deliberately leave behind holes (or introduce new ones) so that future rule abuse can continue. A clever author should be able to read and “drive a -truck through the holes” in the IOCCC rules and IOCCC -guidelines.

+truck through the holes” in the Rules and Guidelines.

At the risk of stating the obvious, this contest is a parody of the software -development process. The IOCCC rules and IOCCC guidelines +development process. The Rules and Guidelines are only part of the overall contest. Even so, one might think the -contest IOCCC rules and IOCCC guidelines process as a parody +contest Rules and Guidelines process as a parody of the sometimes tragic mismatch between what a customer (or marketing) wants and what engineering delivers. Real programmers must face obfuscated and sometimes conflicting, ballooning specifications, and requirements from marketing, sales, product management and even from customers themselves on an all too regular basis. -This is one of the reasons why the IOCCC rules and -IOCCC guidelines are written in obfuscated form.

+This is one of the reasons why the Rules and +Guidelines are written in obfuscated form.

+

Jump to: top

+
+
+

Guidelines for Rule 12 - UTF-8

+

Rule 12 - UTF-8

+
+
+

The IOCCC no longer discourages the use of multibyte UTF-8 characters in C code.

+ +

We DISLIKE C code with trailing control-M’s (\r or \015) that results +in compilation failures.

+

Some non-UNIX/non-Linux tools such as MS Visual C and MS Visual C++ +leave trailing control-M’s on lines. Users of such tools should strip +off such control-M’s before submitting their submissions. In some cases +tools have a “Save As” option that will prevent such trailing control-M’s +being added.

+

If your prog.c is near the +Rule 2a Gross Size and/or +Rule 2b Net Size +limit, you are permitted to NOT end source with a newline. +If you need to do this, please document that in your remarks.md file.

+

If your complains about about not ending in a newline, +please this in your remarks.md file.

Jump to: top

@@ -695,8 +749,8 @@ We will use the GNU make(1) tool, your Makefile, as we in the building and compiling of your submission.

-Your Makefile MUST be compatible with GNU make and we suggest you use -Makefile.example as a template, renamed as Makefile of +Your Makefile MUST be compatible with GNU make and we suggest you use +Makefile.example as a template, renamed as Makefile of course.

See the @@ -758,7 +812,8 @@ Instead of including a large test-suite that requires a lot of files as part of your submission, if your submission doesn’t require the test-suite to be available to run, then in your remarks.md you could include URL where such a test-suite may be downloaded from and how to use the test-suite to test your -submission, assuming it is not reveal who you are. +submission, assuming it is not reveal who you are, eg. do not use a GitHub URL +which contains your username.

If you DO include a tarball then make sure it uses the v7 format. See the @@ -790,9 +845,9 @@ FAQ on “What are the details behind Rule 17 - Use

-

These guideline are hints and suggestions, NOT IOCCC rules.

-

While submissions that violate guideline are allowed, -submissions that remain within the IOCCC guidelines are preferred.

+

These Guidelines are hints and suggestions, NOT Rules.

+

While submissions that violate the Guidelines are allowed, +submissions that remain within the Guidelines are preferred.

You are encouraged to review the following FAQs:

  • How to enter the IOCCC

    • @@ -808,9 +863,8 @@ and then re-uploading it to the same slot number on the The official locale of the IOCCC is C.

    You are encouraged to examine the winners of previous contests.

    -

    Because rules change from year to year, some past winning entries -may be rejected this year.

    -

    What was was unique and novel one year might be ‘old’ the next year.

    +

    Because the Rules change from year to year, some past winning entries +may be rejected this year. What was was unique and novel one year might be ‘old’ the next year.

    A submission is usually examined in a number of ways. We typically apply a number of tests to a submission:

      @@ -863,12 +917,12 @@ an appropriate level of obfuscation.

      Jump to: top

      -

      Our Likes and Dislikes:

      +

      Our Likes and Dislikes

      We VERY MUCH LIKE submissions that use an edited variant of the -example Makefile, as described and linked to in the Makefile section, -renamed as Makefile of course. This makes it easier for the IOCCC judges +example Makefile, as described and linked to in the Makefile section, +renamed as Makefile of course. This makes it easier for the Judges to test your submission. And if your submissions wins, it makes it easier to integrate it into the Official IOCCC winner website.

      We VERY MUCH LIKE submissions that have some educational value. This does NOT mean @@ -908,6 +962,10 @@ If you do include a try.alt.sh then PLEASE remove

      If you don’t have a prog.alt.c, then PLEASE remove the try.alt rule as well.

      +

      Jump to: top

      +
      +

      About C preprocessor

      +

      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 @@ -921,6 +979,12 @@ IOCCC winning entries that did this to compile, we had to update them to not do 

          int this_is_fine;

      and NOT like this:

          this_is_not;       /* <-- Try to avoid implicit type declarations */
      +

      We really DISLIKE submissions that make blatant use of #include of +large data files to get around the source code size limit. This does not mean +#include of standard header files, just data files you provide.

      +

      On 28 January 2007, the Judges rescinded the requirement that the +# in a C preprocessor directive must be the 1st non-whitespace byte.

      +

      About compilers

      We tend to like less a submission that requires either gcc OR clang. We prefer submissions that can compile under BOTH gcc AND clang. Hint!

      @@ -929,7 +993,11 @@ submission’s Makefile are supported by BOTH We DISLIKE the use of obscure compiler flags, especially if gcc and/or clang do not support it. We suggest that you not use any really obscure compiler flags if you can help it.

      +
      +

      About nested functions

      +
      +

      One side effect of the above is that you cannot assume the use of nested functions such as:

           int main() {
@@ -938,12 +1006,12 @@ of nested functions such as:
      
          }
 |        please_dont_submit_this();
      }
      -
-

On 2012 July 20, the IOCCC judges rescinded the encouragement of +

On 2012 July 20, the Judges rescinded the encouragement of nested functions. Such constructions, while interesting and sometimes amusing, will have to wait until they are required by a C standard that are actually implemented in BOTH gcc AND clang.

We DISLIKE submissions that require the use of -fnested-functions.

+

About variadic functions

If your submission uses functions that have a variable number of arguments, be careful. Systems implement va_list in a wide variety of ways. Because of this, a number of operations using va_list are @@ -958,7 +1026,9 @@ not portable and must not be used:

In particular, do not treat va_list variables as if they were a char **.

We DISLIKE the use of varargs.h. Use stdarg.h instead.

+

About I/O

We DISLIKE the use of gets(3). Use fgets(3) instead.

+

About tarballs

We tend to DISLIKE the blatant use of tarballs in an attempt to simply get around the extra file number limit. We realize there may be cases where a tarball containing a number of extra files may be needed. Such a need for a @@ -967,10 +1037,14 @@ tarball MUST be explained in the remarks.md file.< Using a mass of gotos to obfuscate your code has become ‘old’ and is unlikely to make it through the final rounds, if it even gets that far.

-

On 28 January 2007, the Judges rescinded the requirement that the -# in a C preprocessor directive must be the 1st non-whitespace byte.

+
+

About stdlib

+

The exit(3) function returns void. Some broken systems have exit(3) return int; your submission should assume that exit(3) returns a void.

+
+

What it means to be small

+

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 @@ -979,6 +1053,26 @@ programs that are compact, and are instructional.

One line programs should be short one line programs: say around 80 to 132 bytes long. Going well beyond 132 bytes is a bit too long to be called a one-liner in our vague opinion.

+

We suggest that you avoid trying for the ‘smallest self-replicating’ +source. The smallest, a zero byte entry, won in +1994.

+

Programs that claim to be the smallest C source that does something, really +better be the smallest such program or they risk being rejected because +they do not work as documented.

+

We want to get away from source that is simply a compact blob of +bytes. REALLY TRY to be more creative than blob coding. HINT!

+

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 Makefile should not be used to try and get around the size limit. It is +one thing to make use of a several -Ds on the compile line to help out, but it +is quite another to use many bytes of -Ds in order to try and squeeze the +source under the size limit.

+

Please do not use things like gzip(1) to get around the size limit. This was +done years ago; please try to be much more creative.

+

Your source code, post-pre-processing, should not exceed the size of +Microsoft Windows. :-)

+

About environment

We tend to DISLIKE programs that:

  • are very hardware specific
    • @@ -1011,15 +1105,6 @@ Specification (UNIX-like) environment. Therefore do not assume the system has a windows.h include file:

        #include <windows.h>  /* we DISLIKE this */
    -

    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 Makefile should not be used to try and get around the size limit. It is -one thing to make use of a several -Ds on the compile line to help out, but it -is quite another to use many bytes of -Ds in order to try and squeeze the -source under the size limit.

    -

    Your source code, post-pre-processing, should not exceed the size of -Microsoft Windows. :-)

    You should try to restrict commands used in the build file to commands found in Single UNIX @@ -1033,28 +1118,8 @@ absolute one. The intent is to ensure that the building of your program is reasonably portable.

    We prefer programs that are portable across a wide variety of UNIX-like operating systems (e.g., Linux, GNU Hurd, BSD, UNIX, macOS, etc.).

    -

    Don’t forget that the building of your program should be done -WITHOUT human intervention. So don’t do things such as:

    -
        prog: prog.c
-        #echo this next line requires data from standard input
-        cat > prog.c
-        ${CC} prog.c -o prog
    -

    However, you can do something cute such as making your program -do something dumb (or cute) when it is built ‘automatically’, and -when it is run with a human involved, do something more clever. -For example, one could put in their Makefile:

    -
        prog: prog.c
-        ${CC} prog.c -DNON_HUMAN_COMPILE -o prog
-        @echo "See remarks section about alternate ways to compile"
    -

    and then include special notes in your remarks.md file for -alternate / human intervention based building.

    -

    We want to get away from source that is simply a compact blob of -bytes. REALLY TRY to be more creative than blob coding. HINT!

    -

    Please do not use things like gzip(1) to get around the size limit. This was -done years ago; please try to be much more creative.

    -

    We really DISLIKE submissions that make blatant use of #include of -large data files to get around the source code size limit. This does not mean -#include of standard header files, just data files you provide.

    +

    Try to avoid submissions that play music that some people believe is copyrighted +music.

    Did we remember to indicate that programs that blatantly use some complex state machine to do something simple, are boring? We think we did. :-)

    @@ -1064,15 +1129,9 @@ 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! Remember, you can submit more than one submission. See the -    IOCCC rules +Rules for details (in particular, Rule 8 - Submitting requirements).

    -

    We suggest that you avoid trying for the ‘smallest self-replicating’ -source. The smallest, a zero byte entry, won in -1994.

    -

    Programs that claim to be the smallest C source that does something, really -better be the smallest such program or they risk being rejected because -they do not work as documented.

    Please note that the C source below, besides lacking in obfuscation, is NOT the smallest C source file that when compiled and run, dumps core:

        main;
    @@ -1086,6 +1145,21 @@ sort of code will work:

    Initialized char arrays are OK to write over. For instance, this is OK:

        char b[] = "Is this OK";
     b[9] = 'k';     /* modifying an initialized char array is OK */
    +

    We prefer code that can run on either a 64-bit or 32-bit +processor. However, it is UNWISE to assume it will run on an +some Intel-like x86 architecture**.

    +

    While programs that only run in a specific word size are OK, if you have +to pick, choose a 64-bit word size.

    +

    If your submission MUST run only on a 64-bit or 32-bit architecture, +then you MUST specify the -arch on your command line +(see ARCH in the example +Makefile, described in Makefile section). Do not assume a +processor word size without specifying -arch. For example:

    +
        ARCH= -m64
    +

    Note, however, that some platforms will not necessarily support some +architectures. For instance, more recent versions of macOS do NOT support +32-bit, and more than zero Judges use it!

    +

    About X

    X client submissions should be as portable as possible. Submissions that adapt to a wide collection of environments will be favored. For example, don’t depend on a particular type or size of display. @@ -1108,32 +1182,40 @@ open source toolkit that is widely and freely available instead.

    .Xdefaults. If you must do so, be sure to note the required lines in the your remarks.md file. They should also not depend on any particular window manager.

    -

    Try to avoid submissions that play music that some people believe is copyrighted -music.

    -

    While we recognize that UNIX is not a universal operating system, the contest -does have a bias towards such systems. In an effort to expand the scope of the -contest, we phrase our bias to favor the Single UNIX -Specification -(UNIX-like).

    -

    You are well advised to submit code that conforms to the Single UNIX -Specification Version 4.

    -

    To quote the IOCCC judges:

    -

    We LIKE programs that:

    -
      -
    • are as concise and small as they need to be
      • -
    • do something at least quasi-interesting
      • -
    • are portable
      • -
    • are unique or novel in their obfuscation style
      • -
    • make use of a NUMBER OF DIFFERENT TYPES OF OBFUSCATIONS! <== HINT!!
      • -
    • make us laugh and/or throw up :-) (humor really helps!)
      • -
    • make us want to eat good chocolate
      • -
    -

    Some types of programs can’t excel (anti-tm) in some areas. Your -program doesn’t have to excel in all areas, but doing well in several -areas really does help.

    +

    About Curses

    +

    One should restrict libcurses to portable features found on both BSD +and Linux curses.

    +

    +If you do #include <curses.h> make CERTAIN you link in curses (i.e. +-lcurses) and not ncurses (i.e. -lncurses). +

    +

    Jump to: top

    +
    +

    About ASCII TAB

    +
    +

    We DISLIKE the use of ASCII tab characters in markdown files, such as in the required remarks.md file.

    +

    We don’t mind the use of ASCII tab characters in your C code. Feel free +to use ASCII tab characters if that suits your obfuscation needs. If is +perfectly OK to use tab characters elsewhere in your submission, just not in +markdown files as this tends annoy us when it comes time to +rendering your markdown content as it complicates the process.

    +

    If you do use ASCII tab characters in your non-markdown files, be +aware that some people may use a tab stop that is different than the common 8 +character tab stop.

    +

    PLEASE observe our Markdown Guidelines +when forming your submission’s remarks.md file. And if your submission +contains additional markdown files, please follow those same Guidelines for +those files. See also +Rule 4 - Required files, +and the +FAQ on “markdown”.

    +

    Jump to: top

    +
    +

    About remarks.md

    +

    You are better off explaining what your submission does in your remarks.md file section rather than leaving it obscure for the -IOCCC judges as we might miss something and/or be too tired to +Judges as we might miss something and/or be too tired to notice.

    We freely admit that interesting, creative or humorous comments in your remarks.md file help your chances of winning. If you had to @@ -1141,21 +1223,6 @@ read so many twisted submissions, you too would enjoy a good laugh or two. We think the readers of the contest winners do as well. We do read your remarks.md content during the judging process, so it is worth your while to write a remarkable remarks.md file.

    -

    We DISLIKE C code with trailing control-M’s (\r or \015) that results -in compilation failures. Some non-UNIX/non-Linux tools such as -MS Visual C and MS Visual C++ leave trailing control-M’s on lines. -Users of such tools should strip off such control-M’s before submitting -their submissions. In some cases tools have a “Save As” option that will -prevent such trailing control-M’s being added.

    -

    One should restrict libcurses to portable features found on both BSD -and Linux curses.

    -

    -If you do #include <curses.h> make CERTAIN you link in curses (i.e. --lcurses) and not ncurses (i.e. -lncurses). -

    -

    Rule 12 - UTF-8 -no longer discourages the use of UTF-8 -characters in C code.

    It is a very good idea to, in your remarks.md file, tell us why you think your submission is obfuscated. This is particularly true if your submission has some very subtle obfuscations that we might @@ -1171,34 +1238,49 @@ suggest you remark on this point in your remarks.md where you talk about why you think your submission is obfuscated. On the other hand, if you are pushing up against the size limits, you may be forced into creating a dense blob. Such are the trade-offs that obfuscators face!

    -

    We prefer code that can run on either a 64-bit or 32-bit -processor. However, it is UNWISE to assume it will run on an -some Intel-like x86 architecture**.

    -

    While programs that only run in a specific word size are OK, if you have -to pick, choose a 64-bit word size.

    -

    If your submission MUST run only on a 64-bit or 32-bit architecture, -then you MUST specify the -arch on your command line -(see ARCH in the example -Makefile, described in Makefile section). Do not assume a -processor word size without specifying -arch. For example:

    -
        ARCH= -m64
    -

    Note, however, that some platforms will not necessarily support some -architectures. For instance, more recent versions of macOS do NOT support -32-bit, and more than zero judges use it!

    If there are limitations in your submission, you are highly encouraged to note such limitations in your remarks.md file. For example if your submission factors values up to a certain size, you might want to state:

    +

    We LIKE reading remarks.md files, especially if they contain +useful, informative, and even humorous content about your submission. Yes, this +is a hint. :-)

    +

    We RECOMMEND you put a reasonable amount effort into the content of the +remarks.md file: it is a required file for a reason. :-)

    +

    Try to be even more creative!

    +

    Jump to: top

    +

    Miscellaneous

    +

    While we recognize that UNIX is not a universal operating system, the contest +does have a bias towards such systems. In an effort to expand the scope of the +contest, we phrase our bias to favor the Single UNIX +Specification +(UNIX-like).

    +

    You are well advised to submit code that conforms to the Single UNIX +Specification Version 4.

    +

    To quote the Judges:

    +

    We LIKE programs that:

    +
      +
    • are as concise and small as they need to be
      • +
    • do something at least quasi-interesting
      • +
    • are portable
      • +
    • are unique or novel in their obfuscation style
      • +
    • make use of a NUMBER OF DIFFERENT TYPES OF OBFUSCATIONS! <== HINT!!
      • +
    • make us laugh and/or throw up :-) (humor really helps!)
      • +
    • make us want to eat good chocolate
      • +
    +

    Some types of programs can’t excel (anti-tm) in some areas. Your +program doesn’t have to excel in all areas, but doing well in several +areas really does help.

    This submission factors values up 2305567963945518424753102147331756070. Attempting to factor larger values will produce unpredictable results.

    -

    The IOCCC judges might try to factor the value -5, so you want to might state:

    +

    The Judges might try to factor the value -5, so you want to might state:

    This submission factors positive values up 2305567963945518424753102147331756070. Attempting to factor large values will produce unpredictable results.

    -

    However the IOCCC judges might try to also factor 0, so you want to might state:

    +

    However the Judges might try to also factor 0, so you might want to state:

    This submission factors values between 1 and 2305567963945518424753102147331756070. Attempting to factor values outside @@ -1216,7 +1298,7 @@ and doing something interesting. So you might want to code accordingly and state

    This submission factors integers between 1 and 2305567963945518424753102147331756070. Attempting to factor anything else will cause the program to insult your pet fish Eric.

    -

    The IOCCC judges might not have a pet fish named Eric, so you might want to state:

    +

    The Judges might not have a pet fish named Eric, so you might want to state:

    This submission factors integers between 1 and 2305567963945518424753102147331756070. Attempting to factor anything else @@ -1231,28 +1313,6 @@ and state:

    program is given enough time and memory. If the value is not a proper integer, the program might insult a fish named Eric.

    -

    We DISLIKE the use of ASCII tab characters in markdown files, such as in the required remarks.md file.

    -

    We don’t mind the use of ASCII tab characters in your C code. Feel free -to use ASCII tab characters if that suits your obfuscation needs. If is -perfectly OK to use tab characters elsewhere in your submission, just not in -markdown files as this tends annoy us when it comes time to -rendering your markdown content as it complicates the process.

    -

    If you do use ASCII tab characters in your non-markdown files, be -aware that some people may use a tab stop that is different than the common 8 -character tab stop.

    -

    PLEASE observe our IOCCC markdown guidelines -when forming your submission’s remarks.md file. And if your submission -contains additional markdown files, please follow those same guidelines for -those files. See also -Rule 4 - Required files, -and the -FAQ on “markdown”.

    -

    We LIKE reading remarks.md files, especially if they contain -useful, informative, and even humorous content about your submission. Yes, this -is a hint. :-)

    -

    We RECOMMEND you put a reasonable amount effort into the content of the -remarks.md file: it is a required file for a reason. :-)

    -

    Try to be even more creative!

    Jump to: top

    @@ -1281,10 +1341,10 @@ as submissions that use an older version are LIKELY to be for TESTING purposes” in their respective man pages.

    Do NOT use fnamchk(1) command line options that are labeled “for TESTING purposes” in the fnamchk(1) man page.

    -

    Do NOT use chksubmit(1) command line options that are labeled “for the use by the IOCCC judges only” +

    Do NOT use chksubmit(1) command line options that are labeled “for the use by the Judges only” in the chksubmit(1) man page. Similarly do NOT use chkentry(1) command line options marked “for the use -by the IOCCC judges only” in the chkentry(1) man page.

    +by the Judges only” in the chkentry(1) man page.

    To view mkiocccentry toolkit man pages, while your current directory is the top of the source tree:

        man soup/man/man1/mkiocccentry.1
@@ -1426,7 +1486,7 @@ tool to abort with a fatal error.
 
    
 
    See
 FAQ on “How do I report bugs in an mkiocccentry tool?”.
    
-
    See Rule 11 - Legal rule abuse for warnings about ignoring mkiocccentry(1) tool warnings.
    
+
    See Rule 11 - Legal rule abuse for warnings about ignoring mkiocccentry(1) tool warnings.
    
 
    See
 FAQ on “What is the fnamchk tool?”.
    
 
    See
@@ -1446,7 +1506,7 @@ may be found on the “Curio
 of the number of the kernel disk pack of one of the judge’s BESM-6.
    
 
    
 There may or may not be fewer than 2^7+1 reasons why these
-IOCCC guidelines seem obfuscated.
+Guidelines seem obfuscated.
 
    
 
    
 Excessively “dotty” use of the chksubmit(1) or chkentry(1) commands suggests that
@@ -1475,21 +1535,21 @@ after the minute mark is 60.
    
 
    Other windows, on the other hand, might be OK: especially where “X
 marks the spot”. Yet on the third hand, windows are best when they are
 “unseen” (i.e., not dirty). :-)
    
-
    The IOCCC judges, as a group, have a history giving wide degree of latitude
+
    The Judges, as a group, have a history giving wide degree of latitude
 to reasonable submissions. And recently they have had as much longitudinal
 variation as it is possible to have on Earth. :-)
 Other windows, on the other hand, might be OK: especially where “X
 marks the spot”. Yet on the third hand, windows are best when they are
 “unseen” (i.e., not dirty). :-)
    
-
    The IOCCC judges, as a group, have a history giving wide degree of latitude
+
    The Judges, as a group, have a history giving wide degree of latitude
 to reasonable submissions. And recently they have had as much longitudinal
 variation as it is possible to have on Earth. :-)
    
 
    
 
    You are in a maze of twisty guidelines, all different.
    
 
    
-
    There are at least zero IOCCC judges who think that
+
    There are at least zero Judges who think that
 Fideism has little
-or nothing to do with the IOCCC judging process.
    
+or nothing to do with the Judging process.
    
 
    
 
    All generalizations are false, including this one. – Mark Twain
    
 
    
@@ -1526,7 +1586,7 @@ Please try to avoid this specific individual guideline, if it is at all
 
    
 We do not recommend submitting systemd source code to the IOCCC,
 if nothing else because that code is likely to exceed
-Rule 2 - Size.
+Rule 2 - Size restrictions.
 This isn’t to say that another highly compact and obfuscated
 replacement of init(8) would not be an interesting submission.
 
    
@@ -1537,7 +1597,7 @@ is not an original work, unless you one of the
 several mkiocccentry toolkit contributors.
 in which case it is original! :-)
 Even so, most of the programs in the toolkit exceed the
-Rule 2 - Size
+Rule 2 - Size restrictions
 so they wouldn’t qualify for the contest anyway.
 
    
 
    
@@ -1555,32 +1615,18 @@ With respect to nested functions, try chke
 
    Jump to: top
    
 
    
 
    
-
    For more information
    
+
    Further Reading
    
 
    
 
    
-
    For questions or comments about the contest, see Contacting the IOCCC.
    
-
    Be SURE to review the IOCCC Rules and Guidelines as they
-may (and often do) change from year to year.
    
-
    PLEASE be sure you have the current IOCCC rules and
-IOCCC guidelines prior to submitting to the contest.
    
 
    See the Official IOCCC website news for additional information.
    
-
    For the updates and breaking IOCCC news, you are encouraged to follow
-the IOCCC on Mastodon. See our
+
    For questions or comments about the contest, see Contacting the IOCCC.
    
+
    Be SURE to review the current IOCCC Rules and Guidelines as they
+often change year to year. Especially prior to submitting to the contest.
    
+
    For the latest IOCCC news, follow the IOCCC on Mastodon. See our
 FAQ on “Mastodon”
-for more information. Please do note that unless
-you are mentioned by us you will NOT get a notification from the app so you
-should refresh the page even if you do follow us.
    
-
    Check out the Official IOCCC winner website in general.
    
-
    Consider joining the IOCCC discord community via this link:
-https://discord.gg/Wa42Qujwnw
    
-
    See the
-FAQs on “obtaining, compiling, installing and using the mkiocccentry tools”
-and the
-FAQ on “how to enter the IOCCC”
-as that FAQ has important details on
-how to register
-as well as
-how to upload your submission for the IOCCC.
    
+for more information.
    
+
    Also consider joining the IOCCC Discord Server
+for the latest news, discussions about The Rules, questions for the Judges, and C in general.
    
 
    
 
    Jump to: top
 
    
diff --git a/next/guidelines.md b/next/guidelines.md
index 24d5616ad..790a04410 100644
--- a/next/guidelines.md
+++ b/next/guidelines.md
@@ -13,7 +13,7 @@ writing by [contacting the Judges](../contact.html).
 # Guidelines Version
 
 
    
-These Guidelines are version **29.05 2025-12-01**.
+These Guidelines are version **29.06 2025-12-01**.
 
    
 
 
    
@@ -42,7 +42,7 @@ file happens to also be a code for another language.
 We would prefer if you do not use `#include` statements,
 especially `#include` statements just to include lots of data,
 to get around the
-[Rule 2 - Size](rules.html#rule2-size-restrictions) restrictions
+[Rule 2 - Size restrictions](rules.html#rule2-size-restrictions)
 in an excessive way.
 
    
 
@@ -50,7 +50,7 @@ in an excessive way.
 We would prefer if you do not require lots and lots of implicit defines on the C compiler command line
 (i.e., lots of `-Dfoo`, and `-Dcurds=whey` style command line args to the C compiler)
 to get around the
-[Rule 2 - Size](rules.html#rule2-size-restrictions) restrictions
+[Rule 2 - Size restrictions](rules.html#rule2-size-restrictions)
 in an excessive way.
 
    
 
@@ -76,7 +76,7 @@ Jump to: [top](#)
 
    
 
    
 
    
-# Guidelines for [Rule 2 - Size](rules.html#rule2-size-restrictions) restrictions
+# Guidelines for [Rule 2 - Size restrictions](rules.html#rule2-size-restrictions)
 
    
 
    
 
    
@@ -92,7 +92,7 @@ Your submission must satisfy **BOTH** the
 [Rule 2b - Net Size](rules.html#rule2b-net-size) rules.
 
 To check your code against
-[Rule 2 - Size](rules.html#rule2-size) restrictions, use the `iocccentry(1)` tool.
+[Rule 2 - Size restrictions](rules.html#rule2-size), use the `iocccentry(1)` tool.
 For example:
 
 ``` 
@@ -118,22 +118,28 @@ by the minimum required version of `iocccsize(1)` is preferred by the [Judges](.
 
 Make sure `iocccsize` does not flag any issues with your `prog.c`.
 
-**NOTE**: by default `iocccsize` will only report the [Rule 2 - Size](rules.html#rule2-size), unless the
+**NOTE**: by default `iocccsize` will only report the size, unless the
 code surpasses the limit.
 
 There a much less need to `#define` C reserved words in an effort
 to get around the size limits of
-[Rule 2 - Size](rules.html#rule2-size) restrictions
+[Rule 2 - Size restrictions](rules.html#rule2-size)
 because of the `iocccsize(1)` algorithm.
 
 Yes Virginia, **the previous guideline sentence is an important hint**!
 
+Don't expect the [Rule 2 - Size restrictions](rules.html#rule2-size) to
+[change any time soon](../faq.html#size_slow_change).
+
+See the
+FAQ on "[How has the Rule 2 size restrictions rule changed over the years?](../faq.html#size_rule_history)".
+
 
 Jump to: [top](#)
 
 
 
    
-
    
+
    
 # Guidelines for [Rule 3 - Register for the IOCCC](rules.html#rule3-register)
 
    
 
    
@@ -176,7 +182,7 @@ Jump to: [top](#)
 
 
 
    
-
    
+
    
 # Guidelines for [Rule 7 - Original Work](rules.html#rule7-original-work)
 
    
 
    
@@ -209,7 +215,7 @@ Jump to: [top](#)
 
 
 
    
-
    
+
    
 # Guidelines for [Rule 8 - Submitting requirements](rules.html#rule8-submitting-requirements)
 
    
 
    
@@ -222,9 +228,11 @@ Jump to: [top](#)
 
 
    
 
    
+
    
 # Guidelines for [Rule 9 - No interactive compiling allowed](rules.html#rule-9---no-interactive-compiling-allowed)
 
    
 
    
+
    
 
 Don't forget that the building of your program should be done
 **WITHOUT human intervention**.  So don't do things such as:
@@ -255,10 +263,12 @@ Jump to: [top](#)
 
 
 
    
+
    
 
    
 # Guidelines for [Rule 11 - Legal rule abuse](rules.html#rule11-legal-rule-abuse)
 
    
 
    
+
    
 
 We do realize that there are holes in the [Rules](rules.html), and invite
 submitters to attempt to apply creative rule interpretation.  A rule abuse though, even
@@ -338,17 +348,32 @@ Jump to: [top](#)
 
    
 
    
 
-no longer discourages the use of multibyte UTF-8 characters in `C` code.
+The IOCCC no longer discourages the use of multibyte UTF-8 characters in `C` code.
 
 
+
    
+
    
 # Guidelines for [Rule 13 - No carriage returns in prog.c](rules.html#rule-13---no-carriage-returns-in-prog.c)
+
    
+
    
 
 We **DISLIKE** C code with trailing control-M's (`\r` or `\015`) that results
-in compilation failures.  Some non-UNIX/non-Linux tools such as
-MS Visual C and MS Visual C++ leave trailing control-M's on lines.
-Users of such tools should strip off such control-M's before submitting
-their submissions.  In some cases tools have a "Save As" option that will
-prevent such trailing control-M's being added.
+in compilation failures.
+
+Some non-UNIX/non-Linux tools such as MS Visual C and MS Visual C++
+leave trailing control-M's on lines.  Users of such tools should strip
+off such control-M's before submitting their submissions.  In some cases
+tools have a "Save As" option that will prevent such trailing control-M's
+being added.
+
+If your `prog.c` is near the
+[Rule 2a Gross Size](rules.html#rule2a-gross-size) and/or
+[Rule 2b Net Size](rules.html#rule2b-net-size)
+limit, you are permitted to **NOT** end source with a newline.
+If you need to do this, please document that in your `remarks.md` file.
+
+If your complains about about not ending in a newline,
+please this in your `remarks.md` file.
 
 
 Jump to: [top](#)
@@ -1256,7 +1281,7 @@ to proceed with a default, however make sure the default is the **CORRECT** answ
 
    
 
 The `mkiocccentry(1)` tool will use code from `iocccsize(1)` which detects a number of
-issues (such as [Rule 2 - Size](rules.html#rule2-size)) restrictions that you may ignore,
+issues (such as [Rule 2 - Size restrictions](rules.html#rule2-size)) that you may ignore,
 however ignoring such issues **comes with a SIGNIFICANT level of risk!**
 
 Once the tarball is packaged it will
@@ -1502,7 +1527,7 @@ We believe that Mark Twain's quote:
 
    
 We do not recommend submitting [systemd](https://systemd.io) source code to the IOCCC,
 if nothing else because that code is likely to exceed
-[Rule 2 - Size](rules.html#rule2-size).
+[Rule 2 - Size restrictions](rules.html#rule2-size).
 This isn't to say that another highly compact and obfuscated
 replacement of `init(8)` would not be an interesting submission.
 
    
@@ -1514,7 +1539,7 @@ is not an original work, unless you one of the
 [several mkiocccentry toolkit contributors](https://github.com/ioccc-src/mkiocccentry/graphs/contributors).
 in which case it is original!  :-)
 Even so, most of the programs in the toolkit exceed the
-[Rule 2 - Size](rules.html#rule2-size)
+[Rule 2 - Size restrictions](rules.html#rule2-size)
 so they wouldn't qualify for the contest anyway.
 
    
 
diff --git a/next/rules.html b/next/rules.html
index ccc6d61fd..e9371096c 100644
--- a/next/rules.html
+++ b/next/rules.html
@@ -480,7 +480,7 @@ granted provided this copyright and notice are included in its entirety
 and remains unaltered. All other uses MUST receive prior permission in
 writing by contacting the judges.
    
 
    Rules Version
    
-
    These IOCCC Rules are version 29.12 2025-12-01.
    
+
    These IOCCC Rules are version 29.13 2025-12-01.
    
 
    
 The | symbol indicates an change from the previous IOCCC.
 
    
@@ -521,7 +521,7 @@ FAQ on “How can I comment or make a suggestion
 
    
 Your submission MUST be a C program.
 
    
-
    See the Guidelines for Rule 1 - C program.
    
+
    See the Guidelines for Rule 1 - C program.
    
 
    
 
    
 
    
@@ -537,7 +537,7 @@ and
 Rule 2b (Net Size).
 During development this can be checked using iocccsize(1):
    
 
        iocccsize prog.c
    
-
    See the Guidelines for Rule 2 - Size restrictions.
    
+
    See the Guidelines for Rule 2 - Size restrictions.
    
 
    
 
    
 
    
@@ -559,8 +559,8 @@ exceed 4993 bytes.
    
 command line argument to the latest version of the official IOCCC size
 tool (hereby referred to as iocccsize(1)), the value printed MUST
 NOT exceed 2503.
    
-
    NOTE: iocccsize does NOT calculate the filename length. See Rule 17 -
-Use mkiocccentry.
    
+
    NOTE: iocccsize does NOT calculate the filename length.
    
+
    See Rule 17 - Use mkiocccentry.
    
 
    
 
    
 
    Rule 3 - Register for the IOCCC
    
@@ -572,7 +572,7 @@ to the IOCCC. You may register while the contest is pending or
 temporary password, which you MUST change within 14 days.
    
 
    See How to register for the IOCCC.
    
 
    See Entering the IOCCC: the bare minimum you need to know.
    
-
    See Guidelines for Rule 3 - Register for the IOCCC.
    
+
    See Guidelines for Rule 3 - Register for the IOCCC.
    
 
    
 
    
 
    Rule 4 - Required files
    
@@ -645,9 +645,9 @@ a case insensitive filesystem.
    
 
    See Rule 17 - Use mkiocccentry.
    
 
    See the
 FAQ on “What permissions may my files be and what if I need different permissions?”.
    
-
    See the Guidelines on the mkiocccentry toolkit.
    
 
    See the
 FAQ on “What are the detailed recommendations for a submission Makefile?”.
    
+
    See the Guidelines on the mkiocccentry toolkit.
    
 
    
 
    
 
    Rule 5 - Do NOT modify submitted files or filenames or parent directories
    
@@ -696,7 +696,7 @@ You are permitted to use tools to write your code.
 
    
 
    See Rule 16 - Anonymous Judging,
 and
-Guidelines for Rule 7 - Original Work.
    
+Guidelines for Rule 7 - Original Work.
    
 
    
 
    
 
    Rule 8 - Submitting requirements
    
@@ -720,6 +720,7 @@ validate your submission.
 Rule 15 - GNU Makefile,
 and
 Rule 17 - Use mkiocccentry.
    
+
    See Guidelines for Rule 8 - Submitting requirements.
    
 
    
 
    Rule 9 - No interactive compiling allowed
    
 
    
@@ -734,6 +735,7 @@ the make command.
    
 
    NOTE: it is better and more portable to NOT modify the ${CC} variable
 in the Makefile.
    
 
    See Rule 15 - GNU Makefile.
    
+
    See Guidelines for Rule 9 - No interactive compiling allowed.
    
 
    
 
    Rule 10 - Program file permissions
    
 
    
@@ -772,7 +774,7 @@ is rejected.
    
 version, PLEASE indicate that in your remarks.md file of your non-rule
 abusing version so that the Judges don’t think you uploaded a duplicate into a
 wrong slot by mistake.
    
-
    See Guidelines for Rule 11 - Legal rule abuse.
    
+
    See Guidelines for Rule 11 - Legal rule abuse.
    
 
    
 
    
 
    Rule 12 - UTF-8
    
@@ -780,6 +782,7 @@ wrong slot by mistake.
    
 
    
 
    Use of UTF-8 is supported by C89 standard and its updates and so too by the
 IOCCC.
    
+
    See Guidelines for Rule 12 - UTF-8.
    
 
    
 
    Rule 13 - No carriage returns in prog.c
    
 
    
@@ -795,6 +798,7 @@ limits, to NOT end source with a newline. If you
 need to do this, please document that in your remarks.md file and if
 your compiler complains about this, document this too and update your
 Makefile to account for this.
    
+
    See Guidelines for Rule 13 - No carriage returns in prog.c.
    
 
    
 
    Rule 14 - Resubmitting lost submissions
    
 
    
@@ -839,7 +843,7 @@ GNU long name options (such as --example) or extensions like 
 
    See Rule 4 - Required files.
    
 
    See
 FAQ on “What are the detailed recommendations for a submission Makefile?”.
    
-
    See Guidelines for Rule 15 - GNU Makefile.
    
+
    See Guidelines for Rule 15 - GNU Makefile.
    
 
    
 
    
 
    Rule 16 - Anonymous judging
    
@@ -900,7 +904,7 @@ to the command’s -h “print help message”, again notw
 for testing and the IOCCC judges.
 
    
 
    
-The prog.c file should pass the Rule 2 - Size
+The prog.c file should pass the Rule 2 - Size restrictions
 checks performed by iocccsize(1).
 
    
 
    
@@ -915,7 +919,7 @@ version of the mkiocccentry
 
    See Rule 4 - Required files.
    
 
    See the
 FAQ on “What is the mkiocccentry tool, how do I obtain it and how do I use it?”.
    
-
    See the Guidelines for Rule 17 - Use mkiocccentry.
    
+
    See the Guidelines for Rule 17 - Use mkiocccentry.
    
 
    
 
    Rule 18 - Submission license
    
 
    
diff --git a/next/rules.md b/next/rules.md
index 25d4add30..9ed063b65 100644
--- a/next/rules.md
+++ b/next/rules.md
@@ -39,7 +39,7 @@ writing by [contacting the judges](../contact.html).
 
 ## Rules Version
 
-These IOCCC Rules are version **29.12 2025-12-01**.
+These IOCCC Rules are version **29.13 2025-12-01**.
 
 
    
 The | symbol indicates an **change** from the previous IOCCC.
@@ -97,7 +97,7 @@ FAQ on "[How can I comment or make a suggestion on IOCCC rules, guidelines and t
 Your submission **MUST** be a C program.
 
    
 
-See the [Guidelines for Rule 1 - C program](guidelines.html#guidelines-for-rule-1---c-program).
+See the [Guidelines for Rule 1 - C program](guidelines.html#guideline1-c).
 
 
 
    
@@ -120,7 +120,7 @@ During development this can be checked using `iocccsize(1)`:
     iocccsize prog.c
 ```
 
-See the [Guidelines for Rule 2 - Size restrictions](guidelines.html#guideline-2---size).
+See the [Guidelines for Rule 2 - Size restrictions](guidelines.html#guideline2-size).
 
 
 
    
@@ -150,8 +150,9 @@ command line argument to the latest version of the official IOCCC size
 tool (hereby referred to as `iocccsize(1)`), the value printed **MUST
 NOT** exceed **2503**.
 
-**NOTE**: `iocccsize` does **NOT** calculate the filename length. See [Rule 17 -
-Use mkiocccentry](#rule17-mkiocccentry).
+**NOTE**: `iocccsize` does **NOT** calculate the filename length.
+
+See [Rule 17 - Use mkiocccentry](#rule17-mkiocccentry).
 
 
 
    
@@ -170,7 +171,7 @@ See [How to register for the IOCCC](register.html).
 
 See [Entering the IOCCC: the bare minimum you need to know](../quick-start.html#enter).
 
-See [Guidelines for Rule 3 - Register for the IOCCC](guidelines.html#guideline-3---register).
+See [Guidelines for Rule 3 - Register for the IOCCC](guidelines.html#guideline3-register).
 
 
 
    
@@ -265,11 +266,11 @@ See [Rule 17 - Use mkiocccentry](rules.html#rule17-mkiocccentry).
 See the
 FAQ on "[What permissions may my files be and what if I need different permissions?](../faq.html#file_perms)".
 
-See the [Guidelines on the mkiocccentry toolkit](guidelines.html#mkiocccentry_toolkit).
-
 See the
 FAQ on "[What are the detailed recommendations for a submission Makefile?](../faq.html#makefile_details)".
 
+See the [Guidelines on the mkiocccentry toolkit](guidelines.html#mkiocccentry_toolkit).
+
 
 
    
 
    
@@ -334,7 +335,7 @@ You are permitted to use tools to write your code.
 
 See [Rule 16 - Anonymous Judging](rules.html#rule16-anonymous-judging),
 and
-[Guidelines for Rule 7 - Original Work](guidelines.html#guideline-7---original-work).
+[Guidelines for Rule 7 - Original Work](guidelines.html#guideline7-original).
 
 
 
    
@@ -365,6 +366,8 @@ See
 and
 [Rule 17 - Use mkiocccentry](rules.html#rule17-mkiocccentry).
 
+See [Guidelines for Rule 8 - Submitting requirements](guidelines.html#guideline8-submitting).
+
 
 
    
 ## Rule 9 - No interactive compiling allowed
@@ -386,6 +389,8 @@ in the Makefile.
 
 See [Rule 15 - GNU Makefile](rules.html#rule15-gnu-makefile).
 
+See [Guidelines for Rule 9 - No interactive compiling allowed](guidelines.html#guideline9-no-interactive).
+
 
 
    
 ## Rule 10 - Program file permissions
@@ -435,7 +440,7 @@ version, **PLEASE** indicate that in your `remarks.md` file of your non-rule
 abusing version so that the Judges don't think you uploaded a duplicate into a
 wrong slot by mistake.
 
-See [Guidelines for Rule 11 - Legal rule abuse](guidelines.html#guideline-11---abuse).
+See [Guidelines for Rule 11 - Legal rule abuse](guidelines.html#guideline11-abuse).
 
 
 
    
@@ -447,6 +452,8 @@ See [Guidelines for Rule 11 - Legal rule abuse](guidelines.html#guideline-11---a
 Use of UTF-8 is supported by `C89` standard and its updates and so too by the
 IOCCC.
 
+See [Guidelines for Rule 12 - UTF-8](guidelines.html#guideline12-utf8).
+
 
 
    
 ## Rule 13 - No carriage returns in prog.c
@@ -466,6 +473,8 @@ need to do this, please document that in your `remarks.md` file and if
 your compiler complains about this, document this too and update your
 `Makefile` to account for this.
 
+See [Guidelines for Rule 13 - No carriage returns in prog.c](guidelines.html#guideline13-nocr).
+
 
 
    
 ## Rule 14 - Resubmitting lost submissions
@@ -528,7 +537,7 @@ See [Rule 4 - Required files](rules.html#rule4-required-files).
 See
 FAQ on "[What are the detailed recommendations for a submission Makefile?](../faq.html#makefile_details)".
 
-See [Guidelines for Rule 15 - GNU Makefile](guidelines.html#guideline-15---building).
+See [Guidelines for Rule 15 - GNU Makefile](guidelines.html#guideline15-gnu-makefile).
 
 
 
    
@@ -608,7 +617,7 @@ for testing and the IOCCC judges.
 
    
 
 
    
-The `prog.c` file should pass the [Rule 2 - Size](rules.html#rule2-size)
+The `prog.c` file should pass the [Rule 2 - Size restrictions](rules.html#rule2-size)
 checks performed by `iocccsize(1)`.
 
    
 
@@ -628,7 +637,7 @@ See [Rule 4 - Required files](rules.html#rule4-required-files).
 See the
 FAQ on "[What is the mkiocccentry tool, how do I obtain it and how do I use it?](../faq.html#mkiocccentry)".
 
-See the [Guidelines for Rule 17 - Use mkiocccentry](guidelines.html#guideline-17---packaging).
+See the [Guidelines for Rule 17 - Use mkiocccentry](guidelines.html#guideline17-mkiocccentry).
 
 
 
    
diff --git a/sitemap.xml b/sitemap.xml
index 1ba820dcd..36d3b2e56 100644
--- a/sitemap.xml
+++ b/sitemap.xml
@@ -16758,11 +16758,11 @@
 
 
     https://www.ioccc.org/faq.html
-    2025-12-01T05:53:50+00:00
+    2025-12-02T01:59:41+00:00
 
 
     https://www.ioccc.org/faq.md
-    2025-12-01T05:53:50+00:00
+    2025-12-02T01:58:21+00:00
 
 
     https://www.ioccc.org/inc/index.html
@@ -16826,11 +16826,11 @@
 
 
     https://www.ioccc.org/next/guidelines.html
-    2025-12-01T12:23:32+00:00
+    2025-12-02T03:51:13+00:00
 
 
     https://www.ioccc.org/next/guidelines.md
-    2025-12-01T12:23:12+00:00
+    2025-12-02T03:41:39+00:00
 
 
     https://www.ioccc.org/next/index.html
@@ -16870,11 +16870,11 @@
 
 
     https://www.ioccc.org/next/rules.html
-    2025-12-01T10:26:00+00:00
+    2025-12-02T03:51:14+00:00
 
 
     https://www.ioccc.org/next/rules.md
-    2025-12-01T10:21:01+00:00
+    2025-12-02T03:42:10+00:00
 
 
     https://www.ioccc.org/next/submit.html
@@ -16938,7 +16938,7 @@
 
 
     https://www.ioccc.org/status.html
-    2025-12-01T09:18:23+00:00
+    2025-12-02T03:51:32+00:00
 
 
     https://www.ioccc.org/status.json