# cmd **Repository Path**: ChenPi12/cmd ## Basic Information - **Project Name**: cmd - **Description**: A faithful reimplementation of the Windows `cmd.exe` command interpreter for Unix. - **Primary Language**: C - **License**: Not specified - **Default Branch**: main - **Homepage**: None - **GVP Project**: No ## Statistics - **Stars**: 2 - **Forks**: 0 - **Created**: 2026-08-05 - **Last Updated**: 2026-08-30 ## Categories & Tags **Categories**: Uncategorized **Tags**: None ## README # cmd > cmd.exe, the command interpreter for Windows, one of the most widely used > command-line shells in the world. > > But it is not available on Unix-like systems. Why not bring it to Unix to > expand the market? > > -- ChenPi11 **A faithful reimplementation of the Windows `cmd.exe` command interpreter for Unix.** Born on GNU/Linux, runs on **EVERY UNIX-LIKE SYSTEMS** Unfortunately, it does not support Windows and cannot capture the Windows market. **ONLY LIBC and POSIX API required.** **[README: American English](README.md)** | **[README: 简体中文](README.zh_CN.md)** | **[README: 微软式中文](README.zh_MS.md)** | **[README: 八股文](README.zh_WY.md)** ## Supported languages - American English (en_US.UTF-8, default) - Simplified Chinese (zh_CN.UTF-8) - Microsoft translated Chinese (zh_MS.UTF-8) - Classical Chinese (zh_WY.UTF-8) By setting the `LANG`, `LC_MESSAGES`, or `LC_ALL` environment variable, you can change the language of the `cmd` shell. ## Screenshots `cmd` has been verified running on a wide range of operating systems — even classic System V.

_Haiku	_OpenBSD	_PureDarwin
_NetBSD	_FreeBSD	_{System V}
_GNU/Hurd	_macOS	_MSYS2

## Features - **Batch scripting** — `CALL`, `GOTO`, `IF`, `FOR`, `SHIFT`, `%0`..`%9` expansion, `SETLOCAL`/`ENDLOCAL` scoping, and labels. - **Full pipe & redirection support** — `|`, `<`, `>`, `>>`, `2>` with `cmd.exe` precedence rules. - **40+ builtin commands** — `ASSOC`, `COPY`, `DIR`, `ECHO`, `FOR`, `IF`, `SET`, `START`, `TITLE`, `TYPE`, and more. - **Windows-style environment semantics** — case-insensitive `%VAR%` expansion, `%CD%`, `%DATE%`, `%TIME%`, `%ERRORLEVEL%`, `%CMDCMDLINE%`, delayed expansion with `/v:on`. - **Line editing** — bundled linenoise with Emacs bindings, persistent history (`~/.cmd_history`), and TAB file/directory completion. - **AutoRun support** — site-wide/user init scripts from `$PREFIX/etc/cmd/AutoRun/`, plus `AUTOEXEC.BAT` for `COMMAND.COM`. - **Localised UI** — English and Simplified Chinese, selected from the `LC_ALL` / `LC_MESSAGES` / `LANG` environment. - **Two personalities** — `cmd.exe` for the standard interpreter and `COMMAND.COM` with classic MS-DOS AutoExec behaviour. - **No external dependencies** — C89, a POSIX.1 libc, and nothing else. ## Building ### GNU/Linux (GNU Make) ```sh make make install PREFIX=/usr/local ``` ### Generic Unix (including System V) ```sh sh tbuild.sh # uses $CC, defaults to cc. sh tbuild.sh CC=cc V=0 # quiet build with a specific compiler. env SYSV=0 ./tbuild.sh # Disable System V portability flags. ``` The source is STD C89 with no dependencies beyond a POSIX.1-1990 libc. On `tbuild.sh` adds the portability flags (`-DLIBCMD_SYSV=1` and `-DLIBCMD_NO_VSNPRINTF=1`) — see `lsysport.c`. Use SYSV=0 can disable `-DLIBCMD_SYSV=1`. ## Usage ```text cmd [/c|/k] [/s] [/q] [/d] [/a|/u] [/t:{bf|f}] [/e:{on|off}] [/f:{on|off}] [/v:{on|off}] [string] ``` | Option | Description | | :--- | :--- | | `/c string` | Execute `string` and exit | | `/k string` | Execute `string` and remain interactive | | `/s` | Special parsing mode for `/c`/`/k` (strip outer quotes) | | `/q` | Quiet mode; no banner or prompt | | `/d` | Disable AutoRun scripts | | `/a` | ANSI output (default) | | `/u` | Unicode output | | `/t:{bf\|f}` | Set foreground/background colour nibbles, e.g. `/t:0f` | | `/e:{on\|off}` | Enable/disable command extensions | | `/f:{on\|off}` | Enable/disable file-name completion | | `/v:{on\|off}` | Enable/disable delayed expansion | ## Builtin Commands ```text ASSOC BREAK CALL CD / CHDIR CLS COLOR COPY DATE DEL / ERASE DIR DOSKEY ECHO ENDLOCAL EXIT FOR FTYPE GOTO IF MD / MKDIR MKLINK MOVE PATH PAUSE POPD PROMPT PUSHD RD / RMDIR REM REN / RENAME SET SETLOCAL SHIFT START TIME TITLE TYPE VER VERIFY VOL ``` ## Batch Files Batch files (`.bat` and `.cmd`) are fully supported, including `CALL`, `GOTO`, `IF`, `FOR`, `SHIFT`, `%0`..`%9` argument expansion, and `SETLOCAL`/`ENDLOCAL` scoping. Labels use the colon prefix: ```bat @ECHO OFF :again ECHO Hello, %1 SHIFT IF NOT "%~1"=="" GOTO again ``` ## Pipes and Redirection ```text | Pipe stdout of the left command to stdin of the right < file Redirect stdin from file > file Redirect stdout to file (overwrite) >> file Redirect stdout to file (append) 2> file Redirect stderr to file ``` Multiple redirections can be combined on a single command line. ## Files | Path | Purpose | | :--- | :--- | | `~/.cmd_history` | Command history (plain text, one command per line) | | `~/.cmd_assoc` | File extension associations (`ASSOC` / `FTYPE`) | | `$PREFIX/etc/cmd/AutoRun/` | Scripts executed on startup | | `AUTOEXEC.BAT` | Startup script for `COMMAND.COM` | ## Portability `cmd` avoids GNU extensions, designated initialisers, and C99 types where possible. Systems without `fnmatch(3)`, `settimeofday(2)`, `setpriority(2)`, or `open_memstream(3)` are covered by the portability layer in `lsysport.c`. ## License GNU General Public License **version 3 or later** — see [LICENSE](LICENSE). ## Contributing See [CONTRIBUTING](CONTRIBUTING).