Macro: ac_sys_dev_poll

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# ac_sys_dev_poll

## Synopsis

`AC_SYS_DEV_POLL([ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND])`

## Version

1.1 (2001/07/26) Miscellaneous @ ac-archive-0.5.32

## Author

Dave Benson <daveb@ffem.org>

## Description

This macro tests for the presence of /dev/poll support in the build environment. It checks that the needed structure (dvpoll) is available, with the standard fields. /dev/poll is most often seen under Solaris.

Note that it does not attempt to actually open /dev/poll -- you should test for errors when you open it and then fall back to poll() if it is unavailable.

## M4 Source Code

    AC_DEFUN(AC_SYS_DEV_POLL, [AC_CACHE_CHECK(for /dev/poll support, ac_cv_dev_poll,
        AC_TRY_COMPILE([#include <sys/ioctl.h>
    #include <sys/stat.h>
    #include <sys/types.h>
    #include <sys/poll.h>
    #include <sys/devpoll.h>],
    [
      struct dvpoll p;
      p.dp_timeout = 0;
      p.dp_nfds = 0;
      p.dp_fds = (struct pollfd *) 0;
      return 0;
    ],
        ac_cv_dev_poll=yes
        [$1],
        ac_cv_dev_poll=no
        [$2]
        )
      )
    ])