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Date: Sun, 04 Jan 2009 21:34:45 +0100
From: Bob van Loosen <loosen AT xs4all DOT nl>
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Subject: Re: printf goes to serial port?
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Dave Korn wrote:
>   Well... that requires editing every single printf in the whole 
> program, no?
>
>   It might be easier to just at the start of main() open the first 
> three file
> descriptors, so that 0, 1 and 2 are allocated.  If you open 0 from 
> /dev/null
> in read mode and open 1 and 2 for write to /dev/null, all your stdio 
> should
> behave sensibly.  Then if you decide you want the printfs after all, 
> you can
> just change the open to point to a real file and bingo!  Instant log 
> file!
>   
Here's an even better solution:

stdin = fopen("/dev/null", "r");
stdout = fopen("/dev/null", "w");
stderr = fopen("/dev/null", "w");

And then use fprintf on the respective file pointer, this ensures that 
any output will go to /dev/null, even if the file descriptors don't 
start at 0, which can happen (think library constructors).

Bob.

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