The title’s kind of a misnomer. This post is really to help me remember how to get a human-readable string from a Windows error code… I’m finally tired of always having to look it up 
. However, my current situation revolves around determining why a DLL (or *.so on Linux) failed to load, so that’s why this post it titled the way it is.
I like to disable the annoying default dialog that pops up in Windows when a library fails to load.
SetErrorMode(SEM_FAILCRITICALERRORS | SEM_NOGPFAULTERRORBOX | SEM_NOALIGNMENTFAULTEXCEPT | SEM_NOOPENFILEERRORBOX);
Now, here’s the code to get a user friendly text string:
#ifdef WIN32
LPVOID pStr = 0;
DWORD_PTR args[1] = { (DWORD_PTR)pFilename };
FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER |
FORMAT_MESSAGE_FROM_SYSTEM |
FORMAT_MESSAGE_ARGUMENT_ARRAY,
NULL,
GetLastError(),
MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
(LPTSTR)&pStr,
0,
(va_list*)args);
// TODO: Do something with the string pStr here.
LocalFree(pStr);
#else
// TODO: Call dlerror() and do something with the string.
#endif
