FTP4DOS

A Norton Commander-style dual-panel FTP client for MS-DOS running on any x86 machine. The left panel shows the local DOS filesystem; the right panel connects to an FTP server via the mTCP TCP/IP stack — fully keyboard-driven in 80×25 text mode.

Download latest release here: https://github.com/Projanglez/ftp4dos/releases/latest

Features

• Two panels: local (DOS) and remote (FTP, passive mode)
• Navigate directories; view files with F3 (or Enter) — up to 32 KB displayed (remote view downloads temp file first)
• Edit local text files with F4 — minimal full-screen editor (~32 KB, local only)
• Compact size display for large files (M/G units); locale-aware number/date/time formatting from the DOS country setting
• Copy in both directions (F5), including recursive directory trees, with live transfer telemetry (current/average speed, per-file and batch ETA)
• Move (F6) and rename (Alt+F6); recursive move/copy/delete for whole directory trees
• Pause (P) and cancel (ESC) during a running transfer
• Create directories (F7) and recursive delete (F8); Copy/Move/Delete confirm with recursive file/directory counts and total size
• Multiple selection with the Ins key (Norton style) for copy/move/delete
• Configurable per-panel sorting (Alt+F3): by name, extension, size, date or time, ascending or descending — remembered across launches
• Swap the two panels left/right with Ctrl+U (remembered across launches)
• Search / jump-to-name (Alt+F7 or Ctrl+F): jump to the next entry whose name starts with the typed text, wrapping to the top
• Full-screen toggle (Alt+F8): give the active panel the full 80-column width so long remote names stay readable
• Site manager — save and load multiple named FTP connection profiles (host, port, user, password, start directory) in FTP4DOS.SIT, reached from the [Manage...] button in the connect dialog
• File checksums (Alt+F9): CRC32 + MD5 for local and remote files, optionally saved to a file
• Long remote file names kept in full (beyond the 8.3 / 40-column display) and used for transfers; Alt+F2 "Detail" shows the complete name and size
• Long local file names (LFN) on systems with an LFN API (Windows 9x DOS, MS-DOS 7.x, or DOSLFN on plain DOS): the local panel lists and handles long names natively
• UTF-8 remote file names (RFC 2640): names from modern servers are converted to the active DOS codepage (CP437, CP850/858, CP866) for display and local file names; uploads to servers announcing UTF8 in FEAT are encoded back to UTF-8. Override the detected codepage with FTP4DOS_CODEPAGE in MTCP.CFG
• Tunable transfer buffers via MTCP.CFG for maximum throughput on your hardware (see Performance tuning)
• Large remote directories — the default listing holds 512 entries (with a popup when there are more); start with /EXMEM to store the remote list in extended (XMS) or expanded (EMS) memory and browse directories with several thousand files
• Bilingual German/English UI (auto-detected from DOS country setting, or forced on the command line: FTP4DOS /L:EN)

Build requirements

• Open Watcom C/C++ (wmake, wpp, wcc, wasm, wlink)
• Windows or DOS host for cross-compilation
• Target: 16-bit real-mode DOS, Large memory model, 8086+

Building

mTCP is an external dependency, included as a git submodule of the official repository https://github.com/mbbrutman/mTCP, pinned to the 2025-01-10 release tag. Clone with submodules and build with Open Watcom:

git clone --recursive https://github.com/Projanglez/ftp4dos.git
# or, in an existing checkout:
git submodule update --init

wmake          # produces FTP4DOS.EXE
wmake clean    # removes objects and build artifacts

• mTCP home page: http://www.brutman.com/mTCP/mTCP.html

Note: mTCP is compiled with -0 (8086), and the application code likewise uses -0 (compatible with 8086/286/386+). Details are in MAKEFILE and CLAUDE.md.

Running (on the DOS machine)

A packet driver for your network card and an valid mTCP configuration file are required, as well as a valid IP-adress (static or dynamic) via mTCP.

FTP4DOS.EXE

Command-line parameters

FTP4DOS [/L:DE|EN] [/H:HOST] [/P:PORT] [/U:USER] [/W:PASS] [/D:DIR] [/S:ALL|NOPASS|OFF] [/EXMEM[:XMS|EMS]] [/Q] [/MONO|/COLOR]   (or /?)

Both / and - are accepted as the flag prefix. Flags are case-insensitive; values are passed through as-is (username and password are case-sensitive).

Parameter	Description
/L:DE / /L:EN	Force German or English UI
/H:HOST	Connect to HOST automatically on startup
/P:PORT	Port (default 21)
/U:USER	Username (default anonymous)
/W:PASS	Password
/D:DIR	FTP start directory after connect (empty = root)
/S:ALL	Save connection including password to FTP4DOS.SAV (default)
/S:NOPASS	Save connection but not the password
/S:OFF	Do not save this connection
/EXMEM	Store large remote listings in extended/expanded memory (auto: XMS then EMS; force with /EXMEM:XMS or /EXMEM:EMS)
/Q	Skip the splash screen
/MONO	Force monochrome display (MDA/Hercules)
/COLOR	Force color display (default: auto-detect)
/?	Show brief help

Saved connection

After a successful connection, host/port/username (and optionally the password) plus the FTP start directory are stored in FTP4DOS.SAV next to the EXE and pre-filled on the next launch. Use /S:ALL (default), /S:NOPASS, or /S:OFF to control what gets saved; the connect dialog offers the same three choices interactively.

For more than one server, the site manager ([Manage...] in the connect dialog) keeps any number of named profiles in FTP4DOS.SIT.

Security note: Stored passwords are lightly obfuscated (XOR + hex), not encrypted — and FTP transmits passwords in plain text anyway.

Performance tuning

Advanced — totally optional. FTP4DOS works fine out of the box with sensible defaults; only dig into this if you want to squeeze out more throughput on your specific hardware.

Transfer buffer sizes have a large impact on throughput, and the optimal values are hardware-specific (disk speed, CPU, packet driver quality). FTP4DOS reads the following optional settings from your mTCP configuration file (MTCPCFG):

Setting	Range	Default	Description
FTP4DOS_TCP_BUFFER	512–16384	16384	TCP receive buffer (window) of the data connection
FTP4DOS_FILE_BUFFER	512–32768	8192	File I/O buffer: received data is written to disk in blocks of this size (uploads read in the same blocks)
FTP4DOS_CODEPAGE	437/850/858/866	auto	Codepage for UTF-8 file name conversion (default: active DOS codepage)

The mTCP FTP client settings FTP_TCP_BUFFER / FTP_FILE_BUFFER are read as fallbacks, so an already tuned MTCP.CFG works as-is; the FTP4DOS_* keys take precedence. Experiment: larger file buffers help most machines (especially with slow disk I/O), but some setups are faster with small ones. Example:

FTP4DOS_TCP_BUFFER 16384
FTP4DOS_FILE_BUFFER 32768

Key bindings

Key	Action
Tab	Switch active panel
Ctrl+U	Swap panels left/right (remembered)
Ctrl+A	File details (same as Alt+F2)
Ctrl+F	Search / jump to name (same as Alt+F7)
Ctrl+R	Refresh active panel (same as F9)
Arrow keys / PgUp PgDn	Move selection
Home / End	Jump to first / last entry
Ins	Mark entry (for multi-file copy/delete)
* (numpad)	Invert selection
+ (numpad)	Mark files missing or different in the other panel
Enter	Enter directory / view file (same as F3)
Backspace	Go to parent directory
F1	Help
F2	FTP connect / disconnect (with site manager)
Alt+F2	Detail: full name + size of the selected entry
F3	View file (local or remote; max 32 KB)
Alt+F3	Sort the active panel (name/extension/size/date/time, asc/desc)
F4	Edit local file (minimal editor, ~32 KB, no undo/search)
F5	Copy (recursive for directories)
F6	Move (copy then delete source; recursive)
Alt+F6	Rename (in place)
F7	Create directory
Alt+F7	Search / jump to the next name with a prefix
F8	Delete (recursive with confirmation)
Alt+F8	Full-screen the active panel
F9	Refresh the active panel
Alt+F1	Switch local drive
Alt+F9	Checksum (CRC32 + MD5) of the selected file, optionally saved to a file
F10	Quit

License

This project is licensed under the GNU General Public License v3.0 (see LICENSE). It statically links the mTCP library, which is also licensed under the GPLv3.

Third-party code / corresponding source

mTCP © Michael B. Brutman — official home page: http://www.brutman.com/mTCP/mTCP.html

This project builds against the official mTCP, version 2025-01-10, unmodified, referenced as a git submodule of the official repository https://github.com/mbbrutman/mTCP (pinned to the 2025-01-10 release tag). That exact source, together with the source in this repository, constitutes the complete corresponding source for any distributed binary (GPLv3 §6). Published releases include a copy of those mTCP sources as an additional release asset.

Disclaimer

This software is provided without any warranty; use at your own risk. See LICENSE (GPLv3, §15–16).

Development note

This software was developed with the help of an AI coding assistant (Claude Code).