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Sasha



Joined: 17 Nov 2011
Posts: 93
Sasha 13 Nov 2013, 11:13
I have a problem with console output (may be input too, haven't tested).
After closing the output handle it couldn't be opened again, but the function GetStdHandle returns without an error! Here is a test program.


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Post 13 Nov 2013, 11:13
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revolution
When all else fails, read the source


Joined: 24 Aug 2004
Posts: 20363
Location: In your JS exploiting you and your system
revolution 13 Nov 2013, 11:21
If you close one of the standard console handles you can't use the handle again. When you close the handle you also close the pipe between your program and the console app. And trying to open a new pipe would be very tricky if the console app does not know to expect a new pipe from your program.

Basically, don't close the handles if you still need to send and/or receive more data from the console.
Post 13 Nov 2013, 11:21
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revolution
When all else fails, read the source


Joined: 24 Aug 2004
Posts: 20363
Location: In your JS exploiting you and your system
revolution 13 Nov 2013, 11:26
Additional: You can call GetStdHandle multiple times without any issue. It just keeps returning the same handles each time.
Post 13 Nov 2013, 11:26
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Sasha



Joined: 17 Nov 2011
Posts: 93
Sasha 13 Nov 2013, 11:57
So, actually, the standard handle doesn't need to be closed at all.
Post 13 Nov 2013, 11:57
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revolution
When all else fails, read the source


Joined: 24 Aug 2004
Posts: 20363
Location: In your JS exploiting you and your system
revolution 13 Nov 2013, 12:02
Sasha wrote:
So, actually, the standard handle doesn't need to be closed at all.
Correct. You can close them if you want to but then you lose the connection to the host process.
Post 13 Nov 2013, 12:02
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