D bindings for the CFITSIO C library, which provides high-level routines for reading and writing FITS (Flexible Image Transport System) files.

• Direct access to the full CFITSIO C API from D
• Cross-platform: Windows, Linux, macOS
• Easy integration with DUB
• Includes a CLI installer to fetch prebuilt binaries
• Actively maintained and auto-updatable bindings

You must have the native CFITSIO library and its dependencies (e.g., zlib) available for linking and at runtime.
This D package provides the bindings, not the C library itself.

Note:
Due to a current issue, cfitsio-d is not yet available on the official DUB package registry.
You must add it manually to your dub.json or dub.sdl using the GitHub repository URL and a specific commit hash or branch.

In your dub.json:

    "dependencies": {
        "cfitsio-d": {
            "version": "<commit-hash>", 
            "repository": "git+https://github.com/chrischtel/cfitsio-d.git"
        }
    },

In your dub.sdl:

dependency "cfitsio-d" repository="git+https://github.com/chrischtel/cfitsio-d.git" version="<commit-hash>"

Run the installer to download and extract the correct prebuilt binaries for your platform:

dub run cfitsio-d:install

To see all options:

dub run cfitsio-d:install -- --help

Options include:

• --version or -v to specify the CFITSIO version
• --output or -o to set the output directory
• --force or -f to force re-download
• --no-update-dub to skip updating dub.json
• --keep-archive or -k to keep the downloaded archive
• --quiet or -q for less output

The installer will:

• Download the correct binary archive for your OS/arch (and MSVC/MinGW on Windows)
• Extract cfitsio.dll/.so/.dylib and zlib1.dll/.lib if needed
• Optionally update your dub.json with the correct linker flags

• Windows:

  • Use vcpkg or the official CFITSIO site.
  • Make sure you use the correct architecture (x86_64 vs x86) and toolchain (MSVC vs MinGW).
  • Place cfitsio.dll and zlib1.dll next to your executable or in your PATH.
  • Place cfitsio.lib and zlib.lib in your project directory or add their location to your linker path.

• Linux:

  • Install with your package manager:

    sudo apt install libcfitsio-dev
    # or
    sudo dnf install cfitsio-devel
    # or
    sudo pacman -S cfitsio

  • This provides libcfitsio.so in your system library path.

• macOS:

  • Install with Homebrew:

    brew install cfitsio

  • This provides libcfitsio.dylib in your system library path.

"lflags-windows": [
    "/LIBPATH:.", // or your lib directory
    "cfitsio.lib",
    "zlib.lib"
]

• /LIBPATH:. tells the linker to look in the current directory for .lib files.
• Make sure your .lib files are built with MSVC if you use DMD/LDC with the MSVC toolchain.

"lflags-windows": [
    "-L.",
    "-lcfitsio",
    "-lz"
]

• Only use this if you are building everything with MinGW (not recommended for DMD/LDC).

"lflags-posix": [
    "-L.",
    "-lcfitsio"
]

• If installed system-wide, just use -lcfitsio.

• Place cfitsio.dll and zlib1.dll in the same directory as your executable, or in your PATH.
• MSVC vs MinGW:
  • MSVC .lib files are not compatible with MinGW, and vice versa.
  • Always match the architecture (x86_64 vs x86) and toolchain.

• If you build your D project as 64-bit (x86_64), you must use 64-bit cfitsio.dll/.lib and zlib1.dll/.lib.
• If you build as 32-bit, use 32-bit binaries.
• Mixing 32/64-bit or MSVC/MinGW will result in linker or runtime errors.

import cfitsio;
import std.stdio;

void main() {
    fitsfile* fptr = null;
    int status = 0;
    string filename = "!example.fits\0"; // '!' to overwrite if exists

    int ret = ffinit(&fptr, filename.ptr, &status);
    if (ret != 0) {
        writeln("Error initializing FITS file: ", status);
        return;
    }
    writeln("FITS file initialized successfully.");

    // Write a minimal primary HDU (header only, no data)
    int simple = 1;
    int bitpix = 8;
    int naxis = 0;
    int* naxes = null;
    ffphpr(fptr, simple, bitpix, naxis, naxes, 0, 1, 1, &status);

    ffclos(fptr, &status);
    if (status != 0) {
        writeln("Error closing FITS file: ", status);
        return;
    }
    writeln("FITS file closed successfully.");
}

• Linker error: "invalid or corrupt file"

  • Your .lib file is not built with MSVC, or is the wrong architecture.
  • Use the CLI installer or build CFITSIO with the correct toolchain.

• Linker error: /L. not recognized

  • Use /LIBPATH:. for MSVC, not -L..

• Runtime error: Program exited with code -1073741515 (0xC0000135)

  • A required DLL (cfitsio.dll, zlib1.dll, or a Visual C++ runtime DLL) is missing.
  • Place all required DLLs next to your executable or in your PATH.
  • Use Dependencies to check for missing DLLs.

• "library not found" on Linux/macOS

  • Set LD_LIBRARY_PATH (Linux) or DYLD_LIBRARY_PATH (macOS) if the library is not in a standard location.

• Architecture mismatch

  • All binaries (your app, cfitsio.dll, zlib1.dll) must be either all 64-bit or all 32-bit.

• MinGW vs MSVC

  • Do not mix MinGW and MSVC binaries. Use MSVC-built libraries for DMD/LDC on Windows.

The installer can be run with various options:

dub run cfitsio-d:install -- --help

Options:

• --version or -v — Specify CFITSIO version (default: latest)
• --output or -o — Output directory for library files
• --force or -f — Force re-download even if files exist
• --no-update-dub — Do not update dub.json
• --keep-archive or -k — Keep the downloaded archive
• --quiet or -q — Suppress non-error output
• --proxy — Use a proxy for downloads

The installer will:

• Download the correct binary archive for your OS/arch/toolchain
• Extract all required files (cfitsio.dll, cfitsio.lib, zlib1.dll, zlib.lib, etc.)
• Optionally update your dub.json with the correct linker flags

To update to a new CFITSIO version:

• coming soon...

• PRs and issues are welcome!
• Please run the update script and test on your platform before submitting changes.

SEE LICENSE FILE

• CFITSIO Home
• D Language
• dstep (for updating bindings)
• vcpkg
• Dependencies (DLL checker)

Q: I get a linker error about cfitsio.lib being corrupt.
A: You are probably using a MinGW-built .lib with MSVC, or vice versa. Use the CLI installer or build with the correct toolchain.

Q: My program runs but exits with code -1073741515.
A: A required DLL is missing. Use Dependencies to check, and ensure all DLLs are present and match your architecture.

Q: How do I use the installer with custom options?
A:

dub run cfitsio-d:install -- --help

for all options.

If you have any issues, please open an issue on GitHub!