Windows programs are designed to have one choose at compile time if you want stdio handles to be allocated to your program at runtime. This creates a choice at link/compile time:
You get stdin/stdout/stderr HANDLEs allocated, but the system almost always opens a console window of some sort (if one isn't open already). From the perspective of a normal GUI Windows program this console window is just in the way, and closing it can have consequences.
You don't get stdin/stdout/stderr HANDLEs allocated, and allocating them after the fact is tricky. Particularly registering them with the CRT of your process after the CRT has already been static initialized and main() called.
There are some workarounds that people tend to use:
::AllocConsolewill give you a console window, but theHANDLEexperience and piping isn't real.- Linking another copy of your program using
/SUBSYSTEM:CONSOLEis wasteful and adds complexity.
The idea behind conexe is that you invoke conexe, which is a Console subsystem program, in front of your Windows subsystem program in your script or console terminal. Windows will allocate native handles to conexe. Then conexe loads your program via ::LoadLibrary and calls an agreed upon entry point.
A test Windows subsystem program is program is provided. All you have to do is export an entry point that conexe can ::GetProcAddress, and take the customary parameters and return code.
conexe is coded to have as few dependencies as possible, via /NODEFAULTLIB. This means it uses routines from the most base Windows usermode DLLs, and doesn't consume any C/C++ Runtime.
conexe will chdir to the target exe's folder, if it's provided by absolute path.
To the best of my knowledge static imports (kernel loads) and dynamic loads (::LoadLibrary) should retain default load order specified by Dynamic-Link Library Search Order. If you find something that fails to load, then make a minimal repro and writeup an issue.
At first blush, and at the time of this writing:
- Your command line will start with conexe
::GetModuleHandle(NULL)will give you aHMODULEto conexe- Taskman shows you conexe instead of your program
- Lots of other Windows minutae is probably confusing or wrong
I think there are some nice-to-haves to explore here:
- %PATH% lookups for convenience of command line authoring
- Servicing of
::OutputDebugStringWand echo to conexe'sHANDLEs
- Import table patching via Load EXE as DLL: Mission Possible