How to: Determine if an Image is Native or CLR
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The latest version of this topic can be found at How to: Determine if an Image is Native or CLR.
One way to determine whether an image was built for the common language runtime is to use dumpbin/CLRHEADER.
You can also programmatically check whether an image was built for the common language runtime. For more information, see How to: Detect /clr Compilation.
Example
The following sample determines whether an image was built to run on the common language runtime.
// detect_image_type.cpp
// compile with: /clr
using namespace System;
using namespace System::IO;
enum class CompilationMode {Invalid, Native, CLR };
static CompilationMode IsManaged(String^ filename) {
try {
array<Byte>^ data = gcnew array<Byte>(4096);
FileInfo^ file = gcnew FileInfo(filename);
Stream^ fin = file->Open(FileMode::Open, FileAccess::Read);
Int32 iRead = fin->Read(data, 0, 4096);
fin->Close();
// Verify this is a executable/dll
if ((data[1] << 8 | data[0]) != 0x5a4d)
return CompilationMode::Invalid;
// This will get the address for the WinNT header
Int32 iWinNTHdr = data[63]<<24 | data[62]<<16 | data[61] << 8 | data[60];
// Verify this is an NT address
if ((data[iWinNTHdr+3] << 24 | data[iWinNTHdr+2] << 16 | data[iWinNTHdr+1] << 8 | data[iWinNTHdr]) != 0x00004550)
return CompilationMode::Invalid;
Int32 iLightningAddr = iWinNTHdr + 24 + 208;
Int32 iSum = 0;
Int32 iTop = iLightningAddr + 8;
for (int i = iLightningAddr; i < iTop; ++i)
iSum |= data[i];
if (iSum == 0)
return CompilationMode::Native;
else
return CompilationMode::CLR;
}
catch(Exception ^e) {
throw(e);
}
}
int main() {
array<String^>^ args = Environment::GetCommandLineArgs();
if (args->Length < 2) {
Console::WriteLine("USAGE : detect_clr <assembly_name>\n");
return -1;
}
Console::WriteLine("{0} is compiled {1}", args[1], IsManaged(args[1]));
}