curl_multi_wait.3: add example

.\" *                            | (__| |_| |  _ <| |___

.\" *                             \___|\___/|_| \_\_____|

.\" *

.\" * Copyright (C) 1998 - 2014, Daniel Stenberg, <daniel@haxx.se>, et al.

.\" * Copyright (C) 1998 - 2016, 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

.IP CURL_WAIT_POLLOUT

Bit flag to curl_waitfd.events indicating the socket should poll on write

events such as the socket being clear to write without blocking.

.SH EXAMPLE

.nf

CURL *easy_handle;

CURLM *multi_handle;

/* add the individual easy handle */

curl_multi_add_handle(multi_handle, easy_handle);

do {

  CURLMcode mc;

  int numfds;

  mc = curl_multi_perform(multi_handle, &still_running);

  if(mc == CURLM_OK ) {

    /* wait for activity, timeout or "nothing" */

    mc = curl_multi_wait(multi_handle, NULL, 0, 1000, &numfds);

  }

  if(mc != CURLM_OK) {

    fprintf(stderr, "curl_multi failed, code %d.\n", mc);

    break;

  }

  /* 'numfds' being zero means either a timeout or no file descriptors to

     wait for. Try timeout on first occurrence, then assume no file

     descriptors and no file descriptors to wait for means wait for 100

     milliseconds. */

  if(!numfds) {

    repeats++; /* count number of repeated zero numfds */

    if(repeats > 1) {

      WAITMS(100); /* sleep 100 milliseconds */

    }

  }

  else

    repeats = 0;

} while(still_running);

curl_multi_remove_handle(multi_handle, easy_handle);

.fi

.SH RETURN VALUE

CURLMcode type, general libcurl multi interface error code. See

\fIlibcurl-errors(3)\fP