Run Expect scripts from managed code

[inyoursadachine]

Hi, I need to run an Expect script (Expect for Windows of course) from managed code. By "run a script" I mean link (dynamically load) the Tcl and Expect libs (DLLs), create a Tcl_Interp and pass it the script to run. At a high level what does this involve? Can I load (at runtime) the Tcl and Expect DLLs from "unsafe" code? What's the best way to do this? TIA, Matt

[Heath Stewart]

Technically, the CLR loads them. What you can do in C# (or in most managed languages) is P/Invoke the native functions, so long as the Tcl libs are resolvable (i.e., in the current process's current working directory - not the DLL's (though that may be the same as the process's current working directory) - or a directory in the PATH environment variable, the same as all executables in Windows). See the DllImportAttribute documentation in the .NET Framework SDK, as well as Consuming Unmanaged DLL Functions[^]. When you call a P/Invoke method, the CLR loads the native library, gets the proc, pushes your arguments on the stack, and executes the function. The return value is pushed on the stack (typically; depends on calling convention) and returned by the CLR to your managed code. So, you'll need to read the API documentation for Tcl. Chances are there'll be a setup function (to initialize the execution environment) and a function that will accept arguments (including the path to the Tcl script you want to execute). Getting the path to the Tcl script is easy: let the user specify it on the command line, using an OpenFileDialog, hard-code it (bad idea usually), or whatever.

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