[Coco] OS9 Extensions

Bill Pierce ooogalapasooo at aol.com
Wed Sep 23 10:45:21 EDT 2020

Charlie, first, the "bas" extension for Basic09 "should" be a safe assumption (within OS-9) as you would be in OS-9 and typically would not be reading RSDOS disks to start with (there are special cases).
At one time, I found a list of most extensions to use with a utility I was writing and added quite a few more. Here is a list of what I come up with. I know there are more.

TheCOCO Extension List
Thefollowing extensions often show up in the CoCo World. Here's whatthey are:
A OS-9assembly file. Usually used for files intended for the RMA assembler.(ASCII text)
AR OS-9compressed file, using the AR utility by Carl Kreider, (uses LZcompression) (binary)
ARC OS-9or RSDOS file compressed with TC.BIN and later versions of "TheCompressor" series(binary)
ASC Orchestra90files downloaded from the Orchestra90 SIG on Compu-Serve.
ASM OS-9or RSDOS. The assembly language source code from EDTASM or OS-9assembler (ASCII text)
BAC/BCKBackup files generated by backup utilities (binary or ASCII text)
BIN abinary file, usually a machine language program that needs to beLOADMed (binary)
BAS OS-9or RSDOS. A general BASIC file (could be tokenized, or in straightASCII format). In OS-9 this would be a Basic09 source file. (ASCIItext unless tokenized, then binary)
C Normallyused for OS-9 “C” compiler sources (ASCII text)
CAS Virtualcassette file for use with CoCo Emulators (PC binary)
CM3 CoCoMax 3 compressed graphic file. CM3 is a highly efficient horizontaland vertical compressor (or so the literature tells us) (binary)
CNFG/CFGUsually a text file containing the default configuration for aprogram. (can be ASCII text or binary)
EC# Projector-3command file, the # can be 0-9 or A-Z where the character pressedalong with [ALT] from within Projector-3 will perform the functioncoded in the file. MIRROR.ECM is a command that takes the currentpicture and flips it horizontally (binary)
FNT/FONTA file containing font data (binary)
DAT Genericextension for data of some sort (ASCII text or binary)
DOC/DOCSGeneric extension for files that contain information documents abouthow to use a program. Usually a standard text file but canincorporate control codes for display & print used by variousword processors and text editors. (ASCII text)
DSK Althoughnot found on a CoCo disk, the DSK files are common with JeffVavasour's CoCo emulator. The DSK file is a Windows/DOS file thatcontains the data from a real CoCo disk. The DSK file can either bechanged back into a real 5.25 CoCo disk, or used with the emulator.(PC binary)
DSK **There is also a CoCo utility called DSHRINK that will create DSKfiles from a standard CoCo 35 track disk (under RS-DOS). This DSKfile contains the entire contents of the disk. The two DSK files ARENOT interchangeable. ** (binary)
FMT Formatdriver file for the Projector 2 series multiviewer, can be added orremoved from the system disk to customize the program to handlewhatever picture formats you want or have (binary)
GIF GraphicInterchange Format, generally the standard graphic format for ALLcomputers, although being replaced by TIFF (Tagged Image FileFormat). GIF was developed by CompuServe.
GIF 87a is the basicstandard, but it was extended to 89a to include embedded text- thatis, a message/note of text that could be viewed during/after seeingthe picture. The note might be the title, the creator, a BBS orInternet address, etc. GIF89a also added transparency, animation, andtimed looping. (binary)
H Normallyused for OS-9 C compiler header files (ASCCII text)
HLP/HELPGeneric extension for help files (ASKII text)
LIB Normallyuser for OS-9 C compiler library files. (ASCII text)
LZH Identicalto the MS-DOS LZH compression, ported to CoCo (binary)
MAN Filescreated for the OS-9 “Man” manual/documentation utility (ASCIItext w/control codes)
MAX CoCoMax1 and 2 picture format, is close or identical to the old CoCo 2 .BINPMODE format (binary)
MGE ColorMax 3 "compressed" graphic file. MGE used some sort ofalternating compressed/uncompressed runs of data. Rumor has it thatsometimes the compressed file was even larger than if the file hadn'tbeen compressed, so it was advised to keep the compression switchedoff (menu option). Standard 320x192 pictures are 14 granules long(about 30k) (binary)
NIB agraphic file format developed by Rick Cooper for CFDM. FYI, NIB useda rather complex, but efficient method of using two data buffers,fill ing one with information about changes in the current pixel, andthe second with what the change was. The data was then combined andcom pressed again (I think using some sort of RLE) and saved to disk.NIBwas "extended" by (me) Stuart Wyss to be fully backwardscompatible, but to also support embedded text (like GIF89a), 640x192,forced color sets, and color-cycling (to support CoCo Max animation)(binary)
ORC Orchestra90files generated by Model 1, 3, & 4.
PAS Pascalsource files (ASCII text??)
PAK wasa compression developed by G.B. Jansen (not to be confused withEmulator PAK files) (binary)
PAK (notto be confused with G.B. Jansen's PAK) is an MS-DOS extension offiles from Jeff V.s CoCo emulator. A PAK file could either be a"snapshot" of the system, or a program pack. (PC binary)
PAT OS-9pattern file (binary)
PIX Yep,a graphic file, belonging, I think, to Apple Macintosh (binary)
PM4 standard6k/12k PMODE dump, same as the .BIN format but some older versions ofthe Projector series graphics viewers may require this extensioninstead (binary)
PNT/PNTROS-9 pointer file (binary)
RAT TheRAT Graphics Design Package picture format, viewable by the Projectorseries viewers (binary)
REL/ROF OS-9C compiler relocatable object file (binary)
RLE agraphic file compressed using Run Length Encoding (binary)
SQS agraphic file format developed by (me) Stuart Wyss (SQS is short forSquash) FYI, SQS was a sort of "windowing" compressionformat that compared subsequent lines. It worked pretty well.(binary)
SQZ anothergraphic file format developed by Rick Cooper for CFDM (SQZ is shortfor Squeeze) (binary)
SYS OS-9system file. (binary or ASCII text)
TC3 afile/group of files compressed using the TC3 compressor (binary)
TNY graphicfile format for the TINY program (possibly AMIGA format) (binary)
TXT genericextension for text files (ASCII text)
VEF OS-9graphic format, may be compressed or uncompressed. Compressed VEFsare sometimes called "Squashed VEF". (binary)
ZIP Thestandard for file compression in the MS-DOS/Windows world, availablefor CoCo.NOTE: This is a guide only. Programmers often make up their ownextensions, or use one or two regardless of what the file actuallycontains. For example, BIN is a very common extension. It can be aprogram that needs to be run, a low-res picture file, data for aprogram, music, etc. (binary)********************************


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