P4DPython26

Using P4D with Python 2.6, 3.0

Note: This appears to no longer be an issue with recent versions of Python.

Python 2.6 and Python 3.0 rely on Microsoft C++ dynamic link libraries which are installed using Side by Side installation and are no longer placed in the Windows System32 directory.

This affects Delphi programs using P4D. The problem that will occur is that you will not be able to load c-extensions such as _socket.pyd,_ctypes.pyd and the importing of modules such socket and ctypes will fail.

To resolve this you need to add a manifest to your Delphi application. Here is an example of the manifest file that PyScripter uses.

File XP_UAC.manifest

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0">
  <assemblyIdentity
    version="1.0.0.0"
    processorArchitecture="*"
    name="PyScripter"
    type="win32"/>
  <dependency>
    <dependentAssembly>
      <assemblyIdentity
        type="win32"
        name="Microsoft.Windows.Common-Controls"
        version="6.0.0.0"
        processorArchitecture="*"
        publicKeyToken="6595b64144ccf1df"
        language="*"/>
    </dependentAssembly>
  </dependency>
  <dependency>
    <dependentAssembly>
      <assemblyIdentity
        type="win32"
        name="Microsoft.VC90.CRT"
        version="9.0.21022.8"
        processorArchitecture="x86"
        publicKeyToken="1fc8b3b9a1e18e3b"
        language="*"/>
    </dependentAssembly>
  </dependency>  
  <trustInfo xmlns="urn:schemas-microsoft-com:asm.v3">
    <security>
      <requestedPrivileges>
        <requestedExecutionLevel level="asInvoker"/>
      </requestedPrivileges>
    </security>
  </trustInfo>
  <asmv3:application>
    <asmv3:windowsSettings xmlns="http://schemas.microsoft.com/SMI/2005/WindowsSettings">
      <dpiAware>true</dpiAware>
    </asmv3:windowsSettings>
  </asmv3:application>
</assembly>

The key here is the dependency on Microsoft.VC90.CRT.

To use this manifest in Delphi you need to create a file say

File XP_UAC.rc

1 24 ".\XP_UAC.manifest"

then compile the file ito XP_UAC.res using brcc32.exe and link the resulting file into your application.