The Festering Pit of Vile Excretions BBS (3) by The Humble Guys - Technical Dissection

The Festering Pit of Vile Excretions BBS (3) is a real April 1991 MS-DOS BBStro attributed to The Humble Guys. Its apparent red sports-car illustration is a static ANSI/CP437 page signed ANSi Magius ACiD. The 5,353-byte TRYME.COM contains a conventional MZ program, 53 authored output fragments and a tiny ANSI-stream driver.

There is no realtime demo effect behind the screen. The program makes 107 unrolled string calls, sends 3,745 bytes through DOS standard output, and exits immediately. An ANSI console driver interprets 417 CSI commands to place and colour the car, board information and signature.

The earlier research queue associated this file with Predator 2. The examined archive contains only TRYME.COM; it has no game, release note, trainer or companion metadata. This pass therefore preserves it as a genuine standalone BBStro and does not claim a proven parent software release.

Sources

Demozoo identifies the production as an April 1991 MS-DOS BBStro by The Humble Guys and an advert for The Festering Pit. It also notes that the originating ANSI artwork is catalogued as The Festering Pit w/F40. Pouet independently lists the same group, platform, production type and 1991 year. The Magius and ACiD names used here come from the executable's visible art signature, not an otherwise empty catalogue credit section.

Examined Artifact

The archive contains one file:

629f5d507c8eab6ed0cf19190613a9434508642988e5218e76bc5f71260a41b8  the_festering_pit_bbs3.zip
0295ca82aa46b5586cfa50feafb9b4da56e45f96b2b076f78caf45ebd76c9e8f  TRYME.COM  5,353 bytes

The ZIP member timestamp is 22 November 2016 and matches the production's modern catalogue arrival, not its historical release. April 1991 comes from Demozoo.

The .COM suffix is misleading. TRYME.COM begins with MZ, has a 512-byte header and is loaded as an EXE. No packer signature or depacking stub is present.

Complete Silent DOSBox-X Run

The exact executable was launched directly under DOSBox-X 2026.01.02 on 30 August 2026 with machine=svga_s3 and 3,000 fixed cycles. SDL used dummy video and audio host drivers; the DOSBox mixer had nosound=true, and Sound Blaster, MIDI and PC-speaker output were disabled. The program has no sound code.

DX-CAPTURE /v TRYME.COM observed the complete route. DOSBox-X's internal ANSI console support interpreted the emitted control stream, the full car page appeared, and the process returned normally before scheduled input was needed. The resulting diagnostic is 3.025 seconds long because it consists almost entirely of the capture command's post-exit hold. There is no animation or interactive gate to traverse.

The private final frame is an uncropped 720x400 capture, also checked as a nearest-neighbour 720x540 square-pixel presentation. It is not published because one central text row contains a complete historical telephone number. The page's overall visual—a red front-view sports car around a black information panel, with the ANSI/ACiD signature at lower left—is described here without reproducing that contact line.

Exact MZ Layout

The MZ header describes the physical file exactly:

file / declared size               5,353 bytes
header                                512 bytes
load image                          4,841 bytes
relocations                             1
entry CS:IP                     0000:0000
entry file offset                    0200h
stack SS:SP                     012F:0400
minimum allocation                     65 paragraphs
checksum word                       7193h

The 16-bit sum across the complete padded file is FFFFh, so the nonzero MZ checksum is internally consistent. The sole relocation points to load offset 03C8h, the segment immediate used to establish the data segment.

The load image divides cleanly:

0000h..03D7h    984 bytes   entry, output dispatcher and helpers
03D8h..1247h  3,696 bytes   NUL-terminated ANSI/CP437 fragment strings
1248h..12E8h    161 bytes   output mode, parser state, DTA and zeroed runtime tail

The corresponding region hashes are:

2fef1868ab1824ebb65b679b6478eae933f2854ba39a68b9f95f0800a3394284  code
8416aa4713efe434479db1d35facea83420692ed3b836474527b83303c675cdb  ANSI strings
9cc08f0aeee7e98812a2e9663554bea4c468fcf9c46bcb9877532b27a2a8b203  runtime tail
a7075e8d59bf7328b1af660300dfef6cedc6b7c15712214f450f5154b3ac2635  load image

Startup And Relocated Data Segment

The entry begins with two setup calls before the unrolled string list:

0000  call 03B4h           ; memory/data/DTA setup
0003  call 0379h           ; select DOS/ANSI output mode 2
0006  mov  si,0008h
0009  call 028Eh           ; emit ESC [ 2 J
000C  mov  si,000Dh
000F  call 028Eh           ; first long artwork fragment
0012  mov  si,0056h
0015  call 028Eh           ; shared LF,CR string

The startup helper shrinks the process allocation and loads the relocated data segment. Before relocation, the immediate is 003Dh; DOS adds the program load segment through the one MZ fixup at offset 03C8h:

03B4  mov  ax,ds           ; PSP segment
03B6  mov  es,ax
03B8  mov  bx,ss
03BA  sub  bx,ax
03BC  add  bx,0060h
03BF  mov  ah,4Ah
03C1  int  21h             ; resize process block

03C3  mov  es,[002Ch]      ; environment segment from PSP
03C7  mov  ax,003Dh        ; relocated to load segment + 003Dh
03CA  mov  ds,ax
03CC  mov  [0E8Bh],es
03D0  mov  ah,1Ah
03D2  mov  dx,0E99h
03D5  int  21h             ; install private DTA

Runtime DS:0000 therefore corresponds to load offset 03D0h, and the first real string at load offset 03D8h is addressed as DS:0008h. The overlap is intentional: the last eight code bytes sit below the first used data offset.

The Main Program Is An Unrolled Fragment List

From 0006h through 0287h, the main routine contains 107 identical mov si,offset / call 028Eh pairs. Every call targets the same NUL-terminated string printer. There are 55 unique string offsets:

one initial clear-screen string;
53 artwork/cursor fragments;
one shared two-byte LF,CR string at DS:0056h, called 53 times.

The 55 unique strings contain 3,641 bytes. Reusing the newline string after every fragment raises the actual output to exactly 3,745 bytes. There is no loop counter, file read, decompressor or runtime page buffer; the compiler or generator simply emitted the entire call schedule inline.

The first artwork fragment even begins with a second clear and then positions the cursor before drawing the upper car edge:

ESC [ 40 m        black background
ESC [ 2 J         erase display
ESC [ 24 C        move forward 24 columns
ESC [ 0;1;31 m    reset, bright red foreground
33 * CP437 DCh    upper half-block run
ESC [ 2;1 H       cursor to row 2, column 1
ESC [ 19 C        move forward 19 columns
2 * CP437 DCh
ESC [ s           save cursor

Later fragments use ESC[s and ESC[u to save and restore a construction position, absolute H moves for major rows, relative C and A moves for horizontal/vertical overlays, and SGR m commands for colour and intensity.

One-Byte DOS Output Path

Call 0379h stores mode 2 at [0E78h]. The common printer at 028Eh sees that mode and chooses DOS standard output rather than its BIOS fallback:

028E  cmp  byte [0E78h],1
0293  je   02C9h           ; mode 1: BIOS/custom CSI path

0295  mov  dl,[si]
0297  or   dl,dl
0299  je   02C8h           ; NUL terminates this fragment
029B  inc  si
029C  cmp  dl,5Ch          ; optional backslash escape syntax
029F  jne  02C2h
      ...                  ; \# -> ESC, \\ddd -> byte value
02C2  mov  ah,02h
02C4  int  21h             ; one byte to standard output
02C6  jmp  0295h
02C8  ret

The examined strings already contain literal escape and CP437 bytes, so the optional backslash conversions are never used. The path executes DOS function 2 exactly 3,745 times. An installed ANSI console layer consumes the CSI sequences; ordinary CP437 bytes become visible glyphs.

The complete emitted stream hashes to:

6a75b2fdd1eead551c152dbba5e70ef0a5903a5c3cc0b300a40a3e420b1688b5  3,745-byte output stream

ANSI Command Ledger

The stream contains 417 ESC [ control sequences and 53 LF,CR pairs:

Final byte	Count	Role in this page
`m`	271	Select foreground/background colours, brightness and reset state.
`C`	59	Move the cursor right by a counted number of columns.
`s`	27	Save a cursor position before a split fragment.
`u`	27	Restore the saved position for the continuation.
`H`	18	Place the cursor at an absolute row/column.
`A`	13	Move up for a later overlay on a previously visited row.
`J`	2	Clear the display at startup.

The drawing is consequently not a simple top-to-bottom text dump. The first half builds the roof and information panel with paired save/restore fragments; the later fragments revisit rows to close body panels, add wheel and bumper shapes, and place the lower-left signature. CP437 bytes DBh, DCh, DDh, DEh and DFh supply full, upper-half, left-half, right-half and lower-half blocks; box-drawing bytes supply small panel borders.

The final frame is visually dense, but the mechanism is terminal composition: ANSI cursor state plus coloured text cells. No code ever addresses B800h, B000h, A000h, VGA registers or a software framebuffer.

Unused BIOS Fallback

Mode 1 at 02C9h is present but not selected by this entry route. It emits ordinary bytes with BIOS INT 10h/AH=0Eh and recognizes only enough CSI syntax to support clear/mode reset (J) and absolute cursor positioning (H). Its decimal parser at 038Eh accumulates numbers as value = value*10 + digit.

That fallback is useful provenance for the executable generator, but it is not the observed renderer. The default mode-2 path deliberately delegates the full SGR, save/restore and relative-cursor command set to the DOS ANSI console.

Immediate Exit And Persistent Screen

After the last ESC[0m fragment and final LF,CR, main does not wait for a key:

027C  mov  si,0E73h
027F  call 028Eh           ; ESC [ 0 m
0282  mov  si,0056h
0285  call 028Eh           ; LF,CR
0288  mov  ax,4C00h
028B  int  21h             ; normal DOS return

It also does not clear or restore the page. DOS inherits the completed text screen, which is why the final car remains visible throughout the capture command's post-exit hold. The cursor at the lower left belongs to the returned console state, not an intro key prompt.

Runtime-To-Code Concordance

Runtime evidence	Recovered mechanism	Conclusion
A complete red car and central board panel appear in colour text mode	53 stored fragments contain ANSI cursor/SGR commands plus CP437 block characters	The image is terminal artwork, not a bitmap or realtime renderer.
Distant portions of the car settle into one static page almost instantly	Main makes 107 unrolled printer calls; 417 CSI commands revisit rows and columns	The apparent assembly is ANSI cursor composition completed faster than capture cadence, not authored animation.
No key was needed and the capture is almost entirely post-exit hold	Main ends directly with `AX=4C00h` / `INT 21h`	There is no hidden interaction, timeout or second screen.
The screen remains after return to DOS	No cleanup follows the last reset/newline string	Persistence is inherited console memory, not a resident process.
The screen is silent	The only interrupts used are DOS memory/DTA/output/exit and BIOS calls in the unused fallback	No music or sound-effect path exists.
The archive has only `TRYME.COM`	Neither embedded text nor package members name Predator 2	The BBStro is genuine, but the earlier claimed software bundle is not proven by this artifact.

This is a technically modest production, but not a fabricated one. Its value is the unusually transparent preservation boundary: one intact MZ, one signed ANSI work, one exact 3,745-byte console stream and a normal immediate return.