Author:

• Name: Anthony C. Howe
  Location: CA - Canada

To build:

    make all

The author provided an unobfuscated version and there is an alternate version that might feel a bit more familiar to vi(m) users. See Alternate code below.

To use:

    ./ant some_file

NOTE: the file must already exist and not specifying any arg will make the program exit without doing anything.

Try:

    make hill
    ./ant hill

    make mole
    ./ant mole

Alternate code:

The author provided us with an unobfuscated version, ant.alt.c.

The other alternate version, ant.alt2.c changes the commands slightly so that to go to the first column you should enter 0, to go to the last column you should enter $, to quit you should enter q, to go back a word you should enter b and to go forwards a word you should enter w. Also, and perhaps most useful, rather than having to hit ctrl-L (form-feed, \f) to get back to command mode you can use the usual ESC (\x1b); the author explains why this was not originally done in their remarks below. These slight modifications will make it slightly less unwieldy for those familiar with vi(m); the rest was unchanged.

Alternate build:

    make alt

Alternate use:

For the unobfuscated version, use ant.alt as you would ant above; for the other one, use ant.alt2 as you would ant above but with the changes in the input keys described above. See the author’s remarks for the remaining commands.

Judges’ remarks:

The author was kind enough to supply a list of references below, in case you are still confused after read the source! :-)

BTW: you’ve most likely heard the joke that if you want a pseudo-random string of characters you can put a user unfamiliar with vi(m) in a vi(m) session (in insert mode) and ask them to exit. Well in this case you’re likely to have this problem if you ARE a vi(m) user! :-) … especially if you don’t read the information below. This means if you’re reading this in vi(m) you’ll have to exit this like in normal vi(m) and then try the same with ./ant only to fail. :-)

NOTE: to enter form feed you should be able to hit ctrl-L. This will allow you to exit insert mode rather than ESC like in normal vi(m). See the author’s commands section for other commands.

Author’s remarks:

Ant’s Editor vIOCCC91

Text files consists of lines of printable text or tab characters. A line can be of arbitrary length and is delimited by either a newline or the end of file. Carriage return is mapped to newline on input and ignored on output. Tab stops are every eight columns. Non-printable characters may have unpredictable results depending on the implementation of curses.

Commands

    h j k l         left,
                    down,
                    up,
                    right
                    cursor movement
    H J K L         word left,
                    page down,
                    page up,
                    word right
    [ ]             beginning and
                    end of line
    t b             top and bottom
                    of file
    i               enter insert
                    mode, form-feed
                    to quit
    x               delete character
                    under the cursor
    W               write buffer to file
    R               refresh the screen
    Q               quit

Exit status

    0               success
    2               missing edit
                    filename

About this entry

The BUF size should be set at compile time to 32767. This value was used because the Sozobon C compiler for the Atari ST has 16 bit ints and a limit on the size of arrays & structures of 32k. Also the WatCom C compiler for the PC also has 16 bits ints. On machines that have 32 bit ints (most unix boxes), a larger value for BUF could be used.

It is recommend that compact memory model be used on PC class machines. Small memory model may work too provided BUF is not too large.

The character constants '\b', '\f', '\n', '\r', '\t' are used in order to provide more portable code, since the compiler should handle the translation of them into the native character set. Note that '\f' (form-feed) was used to exit insert mode because K&R C had no escape constant for the escape-key.

My goals for this project were to learn and experiment with the Buffer Gap Scheme [Fin80][net90], write a useful and portable program, and meet the requirements of the IOCCC. I initially planned to have a mini curses built-in like John Tromp’s 1989/tromp Tetris entry, however this was not as portable as using a curses library with TERMINFO/TERMCAP support.

I plan to post follow-ups such as unobfuscated versions and bugs fixes to comp.editors. Reposts of the editor.101, gap.doc, and editor.102 can be found in the same group every so often.

This entry will display a file with long lines, but has trouble scrolling the screen with long lines. Paging up and down should work correctly, however.

References:

[Fin80] Craig A. Finseth, “Theory and Practice of Text Editors or
A Cookbook For An EMACS”, TM-165, MIT Lab. for Computer
Science

[KeP81] Kernighan & Plauger, “Software Tools in Pascal”,
Addison-Wesley, 81, chapter 6

[Mil86] Eugene W. Myers & Webb Miller, “Row-replacement Algorithms for Screen Editors”, TR 86-19, Dept. of Computer Science,
U. of Arizona

[MyM86] Eugene W. Myers & Webb Miller, “A simple row-replacement
method”, TR 86-28, Dept. of Computer Science, U. of Arizona

[Mil87] Webb Miller, “A Software Tools Sampler”, Prentice Hall, 87 ISBN 0-13-822305-X, chapter 5

[net90] “Editor 101/102” articles from comp.editors

Primary files

• ant.c - entry source code
• Makefile - entry Makefile
• ant.alt2.c - alternate source code
• ant.orig.c - original source code
• ant.alt.c - author provided unobfuscated code

Secondary files

• 1991_ant.tar.bz2 - download entry tarball
• README.md - markdown source for this web page
• .entry.json - entry summary and manifest in JSON
• .gitignore - list of files that should not be committed under git
• .path - directory path from top level directory
• index.html - this web page

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