Having some trouble with select() call in C Post: 302391899

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Top Forums Programming Having some trouble with select() call in C Post 302391899 by Legend986 on Tuesday 2nd of February 2010 09:50:07 PM

02-02-2010

Registered User

Having some trouble with select() call in C

I have this while loop:

Code:

while (notdone) {

		//Set the timers
		waitd.tv_sec = 5;
		waitd.tv_usec = 0;

		FD_ZERO(&tempreadfds);
		FD_ZERO(&tempwritefds);

		FD_ZERO(&readfds);          /* initialize the read fd set */
		FD_ZERO(&writefds);			/* initialize the write fd set */

		FD_SET(parentfd, &readfds); /* add listener socket fd */
		FD_SET(0, &readfds);        /* add stdin fd (0) */


		tempreadfds = readfds; //make a copy
		tempwritefds = writefds; //make a copy

		rv = select(fdmax+1, &tempreadfds, &tempwritefds, (fd_set*) 0, &waitd);
		if (rv < 0) {
			error("ERROR in select");
		} else if(rv == 0) {
			printf("Timeout occurred! No data after 5 seconds\n");
		}
  
                printf("Select called\n");
		fflush(stdout);
}

I was assuming that "Select called" should be printed every 5 seconds but it gets printed only once. Can someone tell me what mistake I am doing?

Legend986

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graphics::primitive::insets

Graphics::Primitive::Insets(3pm)			User Contributed Perl Documentation			  Graphics::Primitive::Insets(3pm)

NAME

       Graphics::Primitive::Insets - Space between things

DESCRIPTION

       Graphics::Primitive::Insets represents the amount of space that surrounds something.  This object can be used to represent either padding
       or margins (in the CSS sense, one being inside the bounding box, the other being outside)

SYNOPSIS

	 use Graphics::Primitive::Insets;

	 my $insets = Graphics::Primitive::Insets->new({
	   top	   => 5,
	   bottom  => 5,
	   left    => 5,
	   right   => 5
	 });

METHODS

   Constructor
       new Creates a new Graphics::Primitive::Insets.

   Instance Methods
       as_array
	   Return these insets as an array in the form of top, right, bottom and left.

       bottom
	   Set/Get the inset from the bottom.

       equal_to
	   Determine if these Insets are equal to another.

       left
	   Set/Get the inset from the left.

       right
	   Set/Get the inset from the right.

       top Set/Get the inset from the top.

       zero
	   Sets all the insets (top, left, bottom, right) to 0.

AUTHOR

       Cory Watson, "<gphat@cpan.org>"

SEE ALSO

       perl(1)

COPYRIGHT &; LICENSE
       Copyright 2008-2010 by Cory G Watson.

       This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

perl v5.12.3							    2010-08-21					  Graphics::Primitive::Insets(3pm)