text: #ifndef HEADER_CURL_SELECT_H
  #define HEADER_CURL_SELECT_H
  /***************************************************************************
   *                                  _   _ ____  _
   *  Project                     ___| | | |  _ \| |
   *                             / __| | | | |_) | |
   *                            | (__| |_| |  _ <| |___
   *                             \___|\___/|_| \_\_____|
   *
   * Copyright (C) 1998 - 2012, Daniel Stenberg, <daniel@haxx.se>, et al.
   *
   * This software is licensed as described in the file COPYING, which
   * you should have received as part of this distribution. The terms
   * are also available at http://curl.haxx.se/docs/copyright.html.
   *
   * You may opt to use, copy, modify, merge, publish, distribute and/or sell
   * copies of the Software, and permit persons to whom the Software is
   * furnished to do so, under the terms of the COPYING file.
   *
   * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
   * KIND, either express or implied.
   *
   ***************************************************************************/
  
  #include "curl_setup.h"
  
  #ifdef HAVE_SYS_POLL_H
  #include <sys/poll.h>
  #elif defined(HAVE_POLL_H)
  #include <poll.h>
  #endif
  
  /*
   * Definition of pollfd struct and constants for platforms lacking them.
   */
  
  #if !defined(HAVE_STRUCT_POLLFD) && \
      !defined(HAVE_SYS_POLL_H) && \
      !defined(HAVE_POLL_H)
  #undef POLLIN
  #undef POLLPRI
  #undef POLLOUT
  #undef POLLERR
  #undef POLLHUP
  #undef POLLNVAL
  #define POLLIN      0x01
  #define POLLPRI     0x02
  #define POLLOUT     0x04
  #define POLLERR     0x08
  #define POLLHUP     0x10
  #define POLLNVAL    0x20
  
  #ifndef _WINSOCKAPI_
  struct pollfd
  {
  	curl_socket_t fd;
  	short   events;
  	short   revents;
  };
  #endif
  
  
  #endif
  
  #ifndef POLLRDNORM
  #define POLLRDNORM POLLIN
  #endif
  
  #ifndef POLLWRNORM
  #define POLLWRNORM POLLOUT
  #endif
  
  #ifndef POLLRDBAND
  #define POLLRDBAND POLLPRI
  #endif
  
  /* there are three CSELECT defines that are defined in the public header that
     are exposed to users, but this *IN2 bit is only ever used internally and
     therefore defined here */
  #define CURL_CSELECT_IN2 (CURL_CSELECT_ERR << 1)
  
  int Curl_socket_check(curl_socket_t readfd, curl_socket_t readfd2,
                        curl_socket_t writefd,
                        long timeout_ms);
  
  /* provide the former API internally */
  #define Curl_socket_ready(x,y,z) \
    Curl_socket_check(x, CURL_SOCKET_BAD, y, z)
  
  int Curl_poll(struct pollfd ufds[], unsigned int nfds, int timeout_ms);
  
  /* On non-DOS and non-Winsock platforms, when Curl_ack_eintr is set,
   * EINTR condition is honored and function might exit early without
   * awaiting full timeout.  Otherwise EINTR will be ignored and full
   * timeout will elapse. */
  extern int Curl_ack_eintr;
  
  int Curl_wait_ms(int timeout_ms);
  
  #ifdef TPF
  int tpf_select_libcurl(int maxfds, fd_set* reads, fd_set* writes,
                         fd_set* excepts, struct timeval* tv);
  #endif
  
  /* Winsock and TPF sockets are not in range [0..FD_SETSIZE-1], which
     unfortunately makes it impossible for us to easily check if they're valid
  */
  #if defined(USE_WINSOCK) || defined(TPF)
  #define VALID_SOCK(x) 1
  #define VERIFY_SOCK(x) Curl_nop_stmt
  #else
  #define VALID_SOCK(s) (((s) >= 0) && ((s) < FD_SETSIZE))
  #define VERIFY_SOCK(x) do { \
    if(!VALID_SOCK(x)) { \
      SET_SOCKERRNO(EINVAL); \
      return -1; \
    } \
  } WHILE_FALSE
  #endif
  
  #endif /* HEADER_CURL_SELECT_H */
  
  