> For the complete documentation index, see [llms.txt](https://www.pinvoke.dev/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://www.pinvoke.dev/debug/image_optional_header32.md).

# IMAGE\_OPTIONAL\_HEADER32

```csharp
public struct IMAGE_OPTIONAL_HEADER32
{
    public IMAGE_OPTIONAL_HEADER_MAGIC Magic;
    public byte MajorLinkerVersion;
    public byte MinorLinkerVersion;
    public uint SizeOfCode;
    public uint SizeOfInitializedData;
    public uint SizeOfUninitializedData;
    public uint AddressOfEntryPoint;
    public uint BaseOfCode;
    public uint BaseOfData;
    public uint ImageBase;
    public uint SectionAlignment;
    public uint FileAlignment;
    public ushort MajorOperatingSystemVersion;
    public ushort MinorOperatingSystemVersion;
    public ushort MajorImageVersion;
    public ushort MinorImageVersion;
    public ushort MajorSubsystemVersion;
    public ushort MinorSubsystemVersion;
    public uint Win32VersionValue;
    public uint SizeOfImage;
    public uint SizeOfHeaders;
    public uint CheckSum;
    public IMAGE_SUBSYSTEM Subsystem;
    public IMAGE_DLL_CHARACTERISTICS DllCharacteristics;
    public uint SizeOfStackReserve;
    public uint SizeOfStackCommit;
    public uint SizeOfHeapReserve;
    public uint SizeOfHeapCommit;

    [Obsolete]			
    public uint LoaderFlags;

    public uint NumberOfRvaAndSizes;
    public IMAGE_DATA_DIRECTORY DataDirectory;
}
```

[IMAGE\_OPTIONAL\_HEADER\_MAGIC](/debug/image_optional_header_magic.md)

[IMAGE\_SUBSYSTEM](/debug/image_subsystem.md)

[IMAGE\_DLL\_CHARACTERISTICS](/debug/image_dll_characteristics.md)

[IMAGE\_DATA\_DIRECTORY](/debug/image_data_directory.md)