Basic DISM API Sample

The Deployment Image Servicing and Management (DISM) API allows you to build customized solutions on the DISM platform. You can use the DISM API to install, uninstall, configure, and update Windows features, packages, and drivers in a Windows image.

Sample Using Basic Functions

This example shows how to use some basic DISM API functionality including opening an online session, applying an unattend, and getting extended error info.

#include "windows.h"
#include <stdio.h>
#include "DismApi.h"

int _cdecl wmain()
{
    HRESULT hr = S_OK; 
    HRESULT hrLocal = S_OK; 
    DismSession session = DISM_SESSION_DEFAULT; 
    DismSession sessionOnline = DISM_SESSION_DEFAULT; 
    BOOL bMounted = FALSE; 
    DismFeatureInfo *pFeatureInfo = NULL; 
    DismString *pErrorString = NULL; 

    // Initialize the API
    hr = DismInitialize(DismLogErrorsWarningsInfo, L"C:\\MyLogFile.txt", NULL); 
    if( FAILED(hr)) 
    {
        wprintf(L"DismInitialize Failed: %x\n", hr); 
        goto Cleanup; 
    }

    wprintf(L"Mounting: ");

    // Mount a VHD image 
    hr = DismMountImage(L"C:\\Install.VHD",
                        L"C:\\MountPath",
                        1, 
                        NULL, 
                        DismImageIndex, 
                        DISM_MOUNT_READWRITE, 
                        NULL, 
                        NULL, 
                        NULL); 
    if( FAILED(hr)) 
    {
        wprintf(L"\nDismMountImage Failed: %x\n", hr); 
        goto Cleanup; 
    }

    bMounted = TRUE; 
    wprintf(L"Complete.\n\n");

    // Open a session against the mounted image
    hr = DismOpenSession(L"C:\\MountPath",
                         NULL, 
                         NULL, 
                         &session); 
    if( FAILED(hr)) 
    {
        wprintf(L"DismOpenSession Failed: %x\n", hr); 
        goto Cleanup; 
    }

    // Apply an unattend file to the offline image
    hr = DismApplyUnattend(session, 
                           L"C:\\unattend.xml",
                           FALSE); 
    if( FAILED(hr)) 
    {
        wprintf(L"DismApplyUnattend Failed: %x\n", hr); 
        goto Cleanup; 
    }

    // Also open a session against the running operating system (online image) 
    hr = DismOpenSession(DISM_ONLINE_IMAGE, 
                         NULL, 
                         NULL, 
                         &sessionOnline); 
    if( FAILED(hr)) 
    {
        wprintf(L"DismOpenSession Failed: %x\n", hr); 
        goto Cleanup; 
    }

    // Get the feature info for a non-existent feature to demonstrate error
    // functionality
    hr = DismGetFeatureInfo(sessionOnline, 
                            L"ThisIsAFakeFeatureName",
                            NULL, 
                            DismPackageNone, 
                            &pFeatureInfo); 
    if( FAILED(hr)) 
    {
        wprintf(L"DismGetFeatureInfo Failed: %x\n", hr); 

        hrLocal = DismGetLastErrorMessage(&pErrorString); 
        if( FAILED(hrLocal)) 
        {
            wprintf(L"DismGetLastErrorMessage Failed: %x\n", hr); 
            goto Cleanup; 
        }
        else
        {
            wprintf(L"The last error string was: %s\n", pErrorString->Value); 
        }
    }


Cleanup: 

    // Delete the memory associated with the objects that were returned. 
    // pFeatureInfo should be NULL due to the expected failure above, but the
    // DismDelete function will still return success in this case. 
    hrLocal = DismDelete(pFeatureInfo); 
    if( FAILED(hrLocal)) 
    {
        wprintf(L"DismDelete Failed: %x\n", hrLocal); 
    }

    hrLocal = DismDelete(pErrorString); 
    if( FAILED(hrLocal)) 
    {
        wprintf(L"DismDelete Failed: %x\n", hrLocal); 
    }

    // Close the DismSession to free up resources tied to the offline session
    hrLocal = DismCloseSession (session); 
    if( FAILED(hrLocal)) 
    {
        wprintf(L"DismCloseSession Failed: %x\n", hrLocal); 
    }

    // Close the DismSession to free up resources tied to the online session
    hrLocal = DismCloseSession (sessionOnline); 
    if( FAILED(hrLocal)) 
    {
        wprintf(L"DismCloseSession Failed: %x\n", hrLocal); 
    }

    // Unmount the image if is has been mounted.  If the package was successfully added,
    // then commit the changes.  Otherwise, discard the
    // changes
    if (bMounted) 
    {
        hrLocal = DismUnmountImage(L"C:\\MountPath",
                                   DISM_DISCARD_IMAGE, 
                                   NULL, 
                                   NULL, 
                                   NULL); 
        if( FAILED(hrLocal)) 
        {
            wprintf(L"DismUnmountImage Failed: %x\n", hrLocal); 
        }
    }

    // Shutdown the DISM API to free up remaining resources
    hrLocal = DismShutdown();
    if( FAILED(hrLocal)) 
    {
        wprintf(L"DismShutdown Failed: %x\n", hr); 
    }

    wprintf(L"Return code is: %x\n", hr); 
    return hr; 
}

Related topics

DISM API Samples

DISM API Reference

Using the DISM API

Creating a DISM Application

DISM API Troubleshooting