When working with the gsapi.dll, start with the gsapi_revision function, get that working. Then get this api working next.

    private static extern int gsapi_revision(ref GSVersion version, int len);

        gsapi_revision(ref version, Marshal.SizeOf(version));

    private static extern int gsapi_revision(ref GSVersion version, int len);

    Declare Auto Function gsapi_revision Lib "gsdll32.dll" (ByRef pVer As GSVersion, ByVal pSize As Integer) As Integer

The gsapi_revision function takes a reference to a GSVersion structure.

Here is an example of using the gsapi_revision in an object property.

        gsapi_revision(ref gsVer, Marshal.SizeOf(gsVer));

    lResult = gsapi_revision(lVer, Marshal.SizeOf(lVer))

When starting to work with the Ghostscript Interpreter API (gsapi.dll), it is helpful to start by getting the gsapi_revision function to work.

Here is a sample of how the GSVersion structure is filled in by the gsapi_revision function.

Originally this article showed the 'product' and 'copyright' fields as type 'string', but this causes a program crash when calling the gsapi_revision function (tested under VS2013 and 32-bit GPL Ghostscript v9.15).