C# Signature:

/// <summary>
/// This structure is defined at 88 bytes.  However on Windows 7 it is 168 bytes.
/// It seems there is more info added but we don't know what it is.  Be sure to
/// allocate at least 168 bytes to your buffer or it will likely fail.
/// </summary>
[StructLayout(LayoutKind.Sequential, Pack = 1)]
public struct SYSTEM_MEMORY_LIST_INFORMATION // Size=88
{
    public UInt32 ZeroPageCount; // Size=4 Offset=0
    public UInt32 FreePageCount; // Size=4 Offset=4
    public UInt32 ModifiedPageCount; // Size=4 Offset=8
    public UInt32 ModifiedNoWritePageCount; // Size=4 Offset=12
    public UInt32 BadPageCount; // Size=4 Offset=16
    /// <summary>There are 8 priority levels, so array of 8</summary>
    [MarshalAs(UnmanagedType.ByValArray, SizeConst = 8)]
    public UInt32[] PageCountByPriority; // Size=32 Offset=20
    /// <summary>There are 8 priority levels, so array of 8</summary>
    [MarshalAs(UnmanagedType.ByValArray, SizeConst = 8)]
    public UInt32[] RepurposedPagesByPriority; // Size=32 Offset=52
    public UInt32 ModifiedPageCountPageFile; // Size=4 Offset=84
}

VB Signature:

Declare Function SYSTEM_MEMORY_LIST_INFORMATION Lib "ntdll.dll" (TODO) As TODO

User-Defined Types:

None.

Alternative Managed API:

Do you know one? Please contribute it!

Notes:

None.

Tips & Tricks:

Please add some!

Sample Code:

public void Test()
{
    UInt32
        result = 0;

    NativeMethods.SYSTEM_MEMORY_LIST_INFORMATION
        MemoryList;

    UInt32
        returnSize;

    Int32[]
        arr = new Int32[] { (Int32)Commands.MEMORYLIST };

    IntPtr
        buff = Marshal.AllocHGlobal(1024); // should be more than adequate
    try
    {
        result = (UInt32)NativeMethods.NtQuerySystemInformation(NativeMethods.SYSTEM_INFORMATION_CLASS.SystemMemoryListInformation, buff, result, out returnSize);
        if (result != 0)
            // Most likely error is InfoLengthMismatch = 0xc0000004 -- meaning you need to make the buffer larger
            throw new System.ComponentModel.Win32Exception(((NativeMethods.NtStatus)result).ToString());
        MemoryList = (NativeMethods.SYSTEM_MEMORY_LIST_INFORMATION)Marshal.PtrToStructure(buff, typeof(NativeMethods.SYSTEM_MEMORY_LIST_INFORMATION));
    }
    finally
    {
        Marshal.FreeHGlobal(buff);
    }
}

Please edit this page!

Do you have...

• helpful tips or sample code to share for using this API in managed code?
• corrections to the existing content?
• variations of the signature you want to share?
• additional languages you want to include?

Select "Edit This Page" on the right hand toolbar and edit it! Or add new pages containing supporting types needed for this API (structures, delegates, and more).