Thu Apr 28 2011 17:16:21

Asterisk developer's documentation


select.h File Reference

Bitfield expansions for ast_select. More...

#include <sys/time.h>
#include <sys/select.h>
#include <errno.h>
#include "asterisk/compat.h"
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Go to the source code of this file.

Data Structures

struct  ast_fdset

Defines

#define FD_SET(fd, fds)
#define FD_ZERO(a)

Functions

static int ast_select (int nfds, ast_fdset *rfds, ast_fdset *wfds, ast_fdset *efds, struct timeval *tvp)
 Waits for activity on a group of channels.

Variables

unsigned int ast_FD_SETSIZE

Detailed Description

Bitfield expansions for ast_select.

Definition in file select.h.


Define Documentation

#define FD_SET (   fd,
  fds 
)

Definition at line 55 of file select.h.

Referenced by main(), and wait_result().

#define FD_ZERO (   a)

Definition at line 46 of file select.h.

Referenced by ast_poll2(), main(), and wait_result().


Function Documentation

static int ast_select ( int  nfds,
ast_fdset rfds,
ast_fdset wfds,
ast_fdset efds,
struct timeval *  tvp 
) [inline, static]

Waits for activity on a group of channels.

Parameters:
nfdsthe maximum number of file descriptors in the sets
rfdsfile descriptors to check for read availability
wfdsfile descriptors to check for write availability
efdsfile descriptors to check for exceptions (OOB data)
tvptimeout while waiting for events This is the same as a standard select(), except it guarantees the behaviour where the passed struct timeval is updated with how much time was not slept while waiting for the specified events

Definition at line 76 of file select.h.

References errno, and timersub().

Referenced by ast_poll2(), and main().

{
#ifdef __linux__
   return select(nfds, (fd_set *) rfds, (fd_set *) wfds, (fd_set *) efds, tvp);
#else
   int save_errno = 0;
   if (tvp) {
      struct timeval tv, tvstart, tvend, tvlen;
      int res;

      tv = *tvp;
      gettimeofday(&tvstart, NULL);
      res = select(nfds, (fd_set *) rfds, (fd_set *) wfds, (fd_set *) efds, tvp);
      save_errno = errno;
      gettimeofday(&tvend, NULL);
      timersub(&tvend, &tvstart, &tvlen);
      timersub(&tv, &tvlen, tvp);
      if (tvp->tv_sec < 0 || (tvp->tv_sec == 0 && tvp->tv_usec < 0)) {
         tvp->tv_sec = 0;
         tvp->tv_usec = 0;
      }
      errno = save_errno;
      return res;
   }
   else
      return select(nfds, (fd_set *) rfds, (fd_set *) wfds, (fd_set *) efds, NULL);
#endif
}

Variable Documentation

unsigned int ast_FD_SETSIZE

Definition at line 86 of file poll.c.

Referenced by main().