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Top Forums Programming pipe() and poll() problem in C Post 302478752 by Corona688 on Wednesday 8th of December 2010 10:31:37 PM
Old 12-08-2010
Quote:
here's my code, the name variable and error messages are in french but you get the idea.
Not really, I don't. I have no idea what "descripteur" is and why you're writing to it, for example.

It would also help to know what you're trying to do with this command, and what it's actually doing. And maybe minor details like what your operating system is. Because if you're running linux, you could try strace -f ./command parameters to see a trace of system calls as it runs, which will tell you exactly who's waiting for what when.

---------- Post updated at 09:31 PM ---------- Previous update was at 09:03 PM ----------

This isn't right:
Code:
erreur = write ( tubeEntree[1], tampon, strlen( tampon ) );

Not all text is strings. read() doesn't add a null to the end.

Code:
length=read( entrees[0].fd, tampon, 256 );
if(length == 0)
{
        printf("End of file\n");
}
...
erreur = write ( tubeEntree[1], tampon, length );

 

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Imager::Color::Float(3pm)				User Contributed Perl Documentation				 Imager::Color::Float(3pm)

NAME
Imager::Color::Float - Rough floating point sample color handling SYNOPSIS
$color = Imager::Color->new($red, $green, $blue); $color = Imager::Color->new($red, $green, $blue, $alpha); $color = Imager::Color->new("#C0C0FF"); # html color specification $color->set($red, $green, $blue); $color->set($red, $green, $blue, $alpha); $color->set("#C0C0FF"); # html color specification ($red, $green, $blue, $alpha) = $color->rgba(); @hsv = $color->hsv(); # not implemented but proposed $color->info(); DESCRIPTION
This module handles creating color objects used by Imager. The idea is that in the future this module will be able to handle color space calculations as well. A floating point Imager color consists of up to four components, each in the range 0.0 to 1.0. Unfortunately the meaning of the components can change depending on the type of image you're dealing with: o for 3 or 4 channel images the color components are red, green, blue, alpha. o for 1 or 2 channel images the color components are gray, alpha, with the other two components ignored. An alpha value of zero is fully transparent, an alpha value of 1.0 is fully opaque. METHODS
new This creates a color object to pass to functions that need a color argument. set This changes an already defined color. Note that this does not affect any places where the color has been used previously. rgba() This returns the red, green, blue and alpha channels of the color the object contains. info Calling info merely dumps the relevant color to the log. AUTHOR
Arnar M. Hrafnkelsson, addi@umich.edu And a great deal of help from others - see the "README" for a complete list. SEE ALSO
Imager(3), Imager::Color. http://imager.perl.org/ perl v5.14.2 2011-06-06 Imager::Color::Float(3pm)
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