ASSEMBLY_FILE_DETAILED_INFORMATION structure (winnt.h)

The ASSEMBLY_FILE_DETAILED_INFORMATION structure is used by the QueryActCtxW function.

Syntax

typedef struct _ASSEMBLY_FILE_DETAILED_INFORMATION {
  DWORD  ulFlags;
  DWORD  ulFilenameLength;
  DWORD  ulPathLength;
  PCWSTR lpFileName;
  PCWSTR lpFilePath;
} ASSEMBLY_FILE_DETAILED_INFORMATION, *PASSEMBLY_FILE_DETAILED_INFORMATION;

Members

ulFlags

This value is always 0.

ulFilenameLength

Length in bytes of the file name pointed to by lpFileName. The count does not include the terminating null character.

ulPathLength

Length in bytes of the path string pointed to by lpFilePath The count does not include the terminating null character.

lpFileName

Null-terminated string that specifies the name of the file.

lpFilePath

Null-terminated string that specifies the path to the file named in lpFileName.

Remarks

If QueryActCtxW is called with the FileInformationInAssemblyOfAssemblyInActivationContext option, and the function succeeds, the information in the returned buffer is in form of the ASSEMBLY_FILE_DETAILED_INFORMATION structure. The following is an example of a structure used to hold detailed information about the activation context and a call from QueryActCtxW.

PASSEMBLY_FILE_DETAILED_INFORMATION pAssemblyInfo = NULL;
ACTIVATION_CONTEXT_QUERY_INDEX QueryIndex;
BOOL fSuccess = FALSE;
SIZE_T cbRequired;
HANDLE hActCtx = INVALID_HANDLE_VALUE;
BYTE bTemporaryBuffer[512];
PVOID pvDataBuffer = (PVOID)bTemporaryBuffer;
SIZE_T cbAvailable = sizeof(bTemporaryBuffer);

// Request the first file in the root assembly
QueryIndex.ulAssemblyIndex = 1;
QueryIndex.ulFileIndexInAssembly = 0;

if (GetCurrentActCtx(&hActCtx)) {

    // Attempt to use our stack-based buffer first - if that's not large
    // enough, allocate from the heap and try again.
    fSuccess = QueryActCtxW(
        0, 
        hActCtx, 
        (PVOID)&QueryIndex, 
        FileInformationInAssemblyOfAssemblyInActivationContext,
        pvDataBuffer,
        cbAvailable,
        &cbRequired);

    // Failed, because the buffer was too small.
    if (!fSuccess && (GetLastError() == ERROR_INSUFFICIENT_BUFFER)) {

        // Allocate what we need from the heap - fail if there isn't enough
        // memory to do so.        
        pvDataBuffer = HeapAlloc(GetProcessHeap(), 0, cbRequired);
        if (pvDataBuffer == NULL) {
            fSuccess = FALSE;
            goto DoneQuerying;
        }
        cbAvailable = cbRequired;

        // If this fails again, exit out.
        fSuccess = QueryActCtxW(
            0, 
            hActCtx,
            (PVOID)&QueryIndex,
            FileInformationInAssemblyOfAssemblyInActivationContext,
            pvDataBuffer,
            cbAvailable,
            &cbRequired);

    }

    if (fSuccess) {
        // Now that we've found the assembly info, cast our target buffer back to
        // the assembly info pointer.  Use pAssemblyInfo->lpFileName
        pAssemblyInfo = (PASSEMBLY_FILE_DETAILED_INFORMATION)pvDataBuffer;
    }
}

DoneQuerying:
    if (hActCtx != INVALID_HANDLE_VALUE)
        ReleaseActCtx(hActCtx);

    if (pvDataBuffer && (pvDataBuffer != bTemporaryBuffer)) {
        HeapFree(GetProcessHeap(), 0, pvDataBuffer);
        pvDataBuffer = 0;
    }

Requirements

Requirement	Value
Minimum supported client	Windows XP [desktop apps only]
Minimum supported server	Windows Server 2003 [desktop apps only]
Header	winnt.h (include Windows.h)