Mainkt.kt

import java.lang.foreign.*;
import java.lang.invoke.*;

fun main() {
	val arena = Arena.ofConfined()
	val linker = Linker.nativeLinker()
    val lookup = SymbolLookup.libraryLookup("tcl86t", arena).or(SymbolLookup.libraryLookup("tk86t", arena))

    val createInterp = linker.downcallHandle(
        lookup.find("Tcl_CreateInterp").get(),
        FunctionDescriptor.of(ValueLayout.ADDRESS)
    )
    val init = linker.downcallHandle(
        lookup.find("Tcl_Init").get(),
        FunctionDescriptor.of(ValueLayout.JAVA_INT, ValueLayout.ADDRESS)
    )
    val eval = linker.downcallHandle(
        lookup.find("Tcl_Eval").get(),
        FunctionDescriptor.of(ValueLayout.JAVA_INT, ValueLayout.ADDRESS, ValueLayout.ADDRESS)
    )
    val tk_init = linker.downcallHandle(
        lookup.find("Tk_Init").get(),
        FunctionDescriptor.of(ValueLayout.JAVA_INT, ValueLayout.ADDRESS)
    )
    val tk_mainloop = linker.downcallHandle(
        lookup.find("Tk_MainLoop").get(),
        FunctionDescriptor.ofVoid()
    )
    val interp = createInterp.invoke() as MemorySegment

    eval.invoke(interp, arena.allocateFrom("set tcl_library {tcl8.6}"))
    eval.invoke(interp, arena.allocateFrom("set tk_library {tk8.6}"))

    val result0 = init.invoke(interp) as Int
    println(result0)
    val result1 = tk_init.invoke(interp) as Int
    println(result1)

    eval.invoke(interp, arena.allocateFrom("button .b -text \"click me\""))
    eval.invoke(interp, arena.allocateFrom("pack .b"))
    tk_mainloop.invoke()
}