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Re: run.exe flashes non-hidden console window in cygwin64 on Win7Pro-64

On 23 October 2014 06:24, John Wiersba > wrote:
> Maybe I'm confused.  Isn't the purpose of run.exe to start a
> cygwin program without creating a (visible) console window?
> I can just start a cygwin program directly without the indirection of
> run.exe if I don't care about the random flashing console window.
> From the run.exe manpage:
>   run will do this for you.  It works as intermediate and starts a program but makes the console window hidden.

AFAIK, all programs that run in Windows need a window handle in order
to receive events, and to pass to a lot of windows functions. If your
program create a windows before it tries to do anything that requires
a window, that window gets used. When your program does not create its
own windows, the start up code tries to attach you to an existing
console window, and if there is not one, it creates it.

A Windows GUI program starts at winmain(). This entry point does not
have the same requirements as the C standard main() entry point.
Mainly, you do not have the stdin, stdout, and stderr attached to
anything, and you do not have a window. Creating a console or GUI
window is entirely up to your code.

Normally, any non-GUI program will attach to the console window where
it starts. A "dos" type program will attach to the window running the
cmd.exe that started it, and a cygwin program will get attached to the
mintty console window to which your shell is attached,

For both types of non-GUI programs, the msvcrt.dll or cygwin1.dll
runtime code will setup stdin, stdout and stderr before entering
main(). The runtime startup code will create a console window for you
if you did not inherit one from your parent process, and the code will
attach those file pointers to the console window

In any system: Windows, cygwin, linux, or whatever, to create a
windowless process, you close those initial file pointers or file
handles and fork a new process. In the original process, you close
your window if necessary, you call exit(), and the runtime will close
your window if necessary. In the new process, you do what ever you

When you have a cmd.exe window, you use "start" to fire off a new
program and control what happens to its window with command line
When you have a shell in a cygwin console, you use "run.exe" at the
shell prompt.
When you use a shortcut, you have not initial window, so the
msvcrt.dll runtime creates one for you, and uses the properties of the
shortcut to control how that window is created.

At the shell prompt, try the following commands:

$ /cygdrive/c/windows/system32/notepad.exe

$ /cygdrive/c/windows/system32/notepad.exe &

$ run /cygdrive/c/windows/system32/notepad.exe

$ run /cygdrive/c/windows/system32/notepad.exe &

use ps to check how the notepad process is connected to cygwin. Try
exiting the shell after the second command to see why you want to use

Anyway, that's how I think things work. But I may be wrong. It may
give you some ideas on where to look for more correct and/or detailed


Doug Henderson, Calgary, Alberta, Canada

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