NAME ae Ant's Editor May '92 USAGE ae ea where is the text file to edit or create. DESCRIPTION << ae >> is a full screen, VI style text editor. The source should be portable to any environment that provides a K&R C compiler and a CURSES library. << ea >> is a full screen, EMACS style text editor. Text files consists of lines of printable text or tab characters. A line can be of arbitary 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 VI STYLE 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, formfeed to quit x delete character under the cursor X delete character left of the cursor F write buffer to file R refresh the screen Q quit Z switch to EMACS style ? toggle help on/off EMACS STYLE cursor keys left, down, up, right cursor movement ^W ^E word left, word right ^N ^P page down, page up ^A ^D beginning and end of line ^T ^B top and bottom of file backspace delete character left of the cursor delete delete character under the cursor ^F write buffer to file ^R refresh the screen ^C quit ^Z switch to VI style F1 toggle help on/off EXIT STATUS 0 success 1 general error 2 usage error 3 CURSES screen initialization failed INSTALLATION Requires K&R C and a CURSES library for the given target machine. The file creation MODE should be set at compile time to 0600 for Unix systems, or 0 for the Atari ST and PC. 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' (formfeed) was used to exit insert mode because K&R C had no escape constant for the escape-key. HUP should define the name of the fall-back write file. TERMCAP should define for sites that use TERMCAP instead of TERMINFO. POSIX should be defined for systems that have POSIX.1 termios support (which is based on System V termios). Most EBCDIC machines use block mode terminals. This is a problem that has not been addressed and/or tested for. BUGS This editor will display a file with long lines, but has trouble scrolling the screen with long lines. Paging up and down should work correctly, however. The cursor is not positioned correctly on the screen when the file contains multi-glyph characters are displayed, like control codes (^X). 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 Algorithums for Screen Editors", TR 86-19, Dept. of Compter Science, U. of Arizona [MyM86] Eugene W. Myers & Webb Miller, "A simple row-replacement method", TR 86-28, Dept. of Compter 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 FILES ea.man AE May '92 manual Page eaea.c AE May '92 source for dual style editor