Listing the Files that can be Updated

The MsiGetPatchFileList function and PatchFiles property of the Installer Object take a list of Windows Installer patches (.msp files) and return a list of files that can be updated by the patches. The MsiGetPatchFileList function and PatchFiles property are available beginning with Windows Installer 4.0.

Listing Files that can be Updated

The following example shows you how to extract the applicability information for a list of Windows Installer patches (.msp files) using MsiGetPatchFileList. The MsiGetPatchFileList function is provided the product code for the target of the patches and a list of .msp files delimited by semicolons. This example requires Windows Installer 4.0 running on Windows Vista.

#include <windows.h>
#include <stdio.h>
#include <Shellapi.h>
#include <msi.h>
#include <Msiquery.h>
#pragma comment(lib, "msi.lib")
#pragma comment(lib, "shell32.lib")

void CloseMsiHandles(MSIHANDLE* phFileListRec, DWORD dwcFiles);

int __cdecl main()
{
    UINT uiRet = ERROR_SUCCESS;
    int argc;
    WCHAR** argv = CommandLineToArgvW(GetCommandLine(), &argc);
    
    MSIHANDLE *phFileListRec = NULL;
    DWORD dwcFiles = 0;
    WCHAR* szProductCode = argv[1];
    WCHAR* szPatchFileList = argv[2];
    if(ERROR_SUCCESS != (uiRet = MsiGetPatchFileList(szProductCode, szPatchFileList, &dwcFiles, &phFileListRec)))
    {
        printf("MsiGetPatchFileListW(%S, ...) Failed with:%d", szProductCode, uiRet);
        return uiRet;
    }
    
    DWORD cchBuf = 1;
    DWORD cchBufSize = 1;
    WCHAR* szBuf = new WCHAR[cchBufSize];
    if (!szBuf)
    {
        printf("Failed to allocate memory");
        CloseMsiHandles(phFileListRec, dwcFiles);
        return ERROR_OUTOFMEMORY;
    }
    memset(szBuf, 0, sizeof(WCHAR)*cchBufSize);
    
    for(unsigned int i = 0; i < dwcFiles; i++)
    {
        cchBuf = cchBufSize;
        while(ERROR_MORE_DATA == (uiRet = MsiRecordGetString(phFileListRec[i], 0, szBuf, &cchBuf)))
        {
            if (szBuf)
                delete[] szBuf;
            cchBufSize = ++cchBuf;
            szBuf = new WCHAR[cchBufSize];
            if (!szBuf)
            {
                printf("Failed to allocate memory");
                CloseMsiHandles(phFileListRec, dwcFiles);
                return ERROR_OUTOFMEMORY;
            }
        }
        
        if(uiRet != ERROR_SUCCESS)
        {
            printf("MsiRecordGetString(phFileListRec[%d] with %d", i, uiRet);
            CloseMsiHandles(phFileListRec, dwcFiles);
            if (szBuf)
                delete[] szBuf;
            return uiRet;
        }
        else
        {
            printf("File %d:%S\n", i, szBuf);
        }            
    }

    CloseMsiHandles(phFileListRec, dwcFiles);
    if (szBuf)
        delete[] szBuf;
    return 0;
}

void CloseMsiHandles(MSIHANDLE* phFileListRec, DWORD dwcFiles)
{
    if (!phFileListRec)
        return;
    
    for (unsigned int i = 0; i < dwcFiles; i++)
    {
        if (phFileListRec[i])
            MsiCloseHandle(phFileListRec[i]);
    }    
}
//

The following example shows you how to extract the applicability information for a list of Windows Installer patches (.msp files) using PatchFiles property of the Installer Object. The PatchFiles property is provided the product code for the target of the patches and a list of .msp files delimited by semicolons. This example requires Windows Installer 4.0 running on Windows Vista.

Dim FileList
Dim installer : Set installer = Nothing
Dim argCount:argCount = Wscript.Arguments.Count

Set installer = Wscript.CreateObject("WindowsInstaller.Installer")

If (argCount > 0) Then
    sProdCode = Wscript.Arguments(0)
    sPatchPckgPath = Wscript.Arguments(1)
    Set FileList = installer.PatchFiles (sProdCode, sPatchPckgPath)
    For each File in FileList
           Wscript.Echo "Affected file: " & File
    Next
Else
    Usage
End If

Sub Usage
    Wscript.Echo "Windows Installer utility to list files updated by a patch for an installed product" &_
    vbNewLine & " 1st argument is the product code (GUID) of an installed product" &_
    vbNewLine & " 2nd argument is the list of patches" &_
    vbNewLine &_
    vbNewLine & "Copyright (C) Microsoft. All rights reserved."
    Wscript.Quit 1
End Sub