Tcl cffi package

The Tcl cffi package permits calling C functions in shared libraries from within Tcl scripts via either the libffi or dyncall open source libraries. The package supports Tcl 8.6 and 9.0+.

The source repository is at https://github.com/apnadkarni/tcl-cffi.

Documentation is at https://cffi.magicsplat.com. Some additional tutorial material is available at https://www.magicsplat.com/blog/tags/cffi/ and the samples in https://github.com/apnadkarni/tcl-cffi/tree/main/examples.

Source distributions and binary packages for some platforms can be downloaded from https://sourceforge.net/projects/magicsplat/files/cffi. The binary packages for Windows require the VC++ runtime and UCRT be present on the system. These will already be installed on Windows 10 and later. For Windows 7 and 8.x, download if necessary from https://learn.microsoft.com/en-us/cpp/windows/latest-supported-vc-redist and https://support.microsoft.com/en-gb/topic/update-for-universal-c-runtime-in-windows-c0514201-7fe6-95a3-b0a5-287930f3560c.

Building

To build the package from the source, see BUILD.md in the repository or source distribution.

About the package

Major features of the package are

• Implicit conversions of numerics, strings, structs and arrays
• Safety mechanisms for pointers
• Encoding of string values passed and returned from C functions
• Exception generation based on C function return values
• Proc-like argument processing with defaults, error messages etc.
• Utilities for managing memory and conversion to native formats
• Extensible type aliases and enums
• Introspection

Limitations in the current version include

• No support for asynchronous callbacks

Version history

See the Change log.