Closing console window

[golite]

I have a console window that starts up and runs with my Windows app.
I currently have to close the windows app and then close the console also.
Is there a way to close the console window through the WM_CLOSE command?

I am interested in learning how Pelles makes the console stay active. I used to have to cause the console to stay open by using some kind of read or get command.

[jj2007]

If I build a standard GUI app (subsystem windows) and insert
   AllocConsole();
somewhere at the beginning of main(), the console window closes when I close the GUI window.

How do you get the console window?

[TimoVJL]

I have a console window that starts up and runs with my Windows app.
I currently have to close the windows app and then close the console also.
Is there a way to close the console window through the WM_CLOSE command?

I am interested in learning how Pelles makes the console stay active. I used to have to cause the console to stay open by using some kind of read or get command.

This happens only in PellesC IDE ?, (IDE feature to commandline programs)

How do you get the console window?

Just use this in GUI program (UNICODE)

Code Select Expand

...
#pragma comment(linker, "-subsystem:console")
#pragma comment(linker, "-entry:wWinMainCRTStartup")
...

[jj2007]

Just use this in GUI program (UNICODE)

Code Select Expand

...
#pragma comment(linker, "-subsystem:console")
#pragma comment(linker, "-entry:wWinMainCRTStartup")
...

Yes, this works fine, but it produces the behaviour the OP didn't want, i.e. the console remains open until you press a key. AllocConsole behaves better in this respect, but of course, you need an alternative to printf:
   AllocConsole();
   WriteConsole(GetStdHandle(STD_OUTPUT_HANDLE), "Hello", 5, 0, 0);

[golite]

I now have removed the pragma statements and I only need the AllocConsole() and the WriteConsole() to achieve my intentions. This does the trick well.

Thanks Again.

[TimoVJL]

In that way you loose that log in new console.
Simple TRACE macro:

Code Select Expand

#ifndef NDEBUG
//#define TRACE(x) OutputDebugString(x)
#define TRACE(x) WriteStdOut((x))
void __cdecl WriteStdOut(TCHAR *szTxt)
{
static HANDLE hStdOut = 0;
if (!hStdOut) {
AllocConsole();
hStdOut = GetStdHandle(STD_OUTPUT_HANDLE);
}
WriteConsole(hStdOut, szTxt, lstrlen(szTxt), 0, 0);
}
#else
#define TRACE(x)
#endifUsage:

Code Select Expand

TRACE("My TRACE comment\n");

[czerny]

This is an example I have found on the net. printf() is working.

Only problem I see so far is scanf(). It looses the first character of the input. 123 gives 23. 'Test' gives 'est'.

[frankie]

Add a flush of stdin:

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// redirect unbuffered STDIN to the console
lStdHandle = (long)GetStdHandle(STD_INPUT_HANDLE);
hConHandle = _open_osfhandle(lStdHandle, _O_TEXT | _O_RDONLY);
fp = _fdopen( hConHandle, "r" );
*stdin = *fp;
setvbuf( stdin, NULL, _IONBF, 0 );
fflush(stdin); //Add Flush


[czerny]

Thanks!

[aardvajk]

You don't need 6 lines to redirect a stream, 3 will do them all, without having to employ the undefined behaviour of fflush(stdin)

Code Select Expand


freopen("CONIN$", "r", stdin);
freopen("CONOUT$", "w", stdout);
freopen("CONOUT$", "w", stderr);


[frankie]

You don't need 6 lines to redirect a stream, 3 will do them all, without having to employ the undefined behaviour of fflush(stdin)

Yes you're right , for std-C the statement has an undefined behaviour. But in WINNT it is an extension to the standard.
From MS here

Code Select Expand


   // You must flush the input buffer before using gets.
   // fflush on input stream is an extension to the C standard


Code Select Expand


freopen("CONIN$", "r", stdin);
freopen("CONOUT$", "w", stdout);
freopen("CONOUT$", "w", stderr);


This doesn't work.
freopen works when stdin, stdout and stderr already  refers to valid opened streams, that is true when you start a console program, but fails when allocating a console in a GUI subsystem.
When you allocate a console from a GUI program the standard streams don't point to valid files while the allocated console have opened its own streams.
The long code scope is then to collect the actual OS file handle and associate it to C-runtime streams stdin, stdout, stderr.
This tecnique is MS original as showed here