curl_multi_timeout(3)

1curl_multi_timeout(3)           libcurl Manual           curl_multi_timeout(3)
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NAME

6       curl_multi_timeout - how long to wait for action before proceeding
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SYNOPSIS

9       #include <curl/curl.h>
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11       CURLMcode curl_multi_timeout(CURLM *multi_handle, long *timeout);
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DESCRIPTION

14       An   application   using   the  libcurl  multi  interface  should  call
15       curl_multi_timeout(3) to figure out how long it should wait for  socket
16       actions - at most - before proceeding.
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18       Proceeding means either doing the socket-style timeout action: call the
19       curl_multi_socket_action(3) function with the sockfd  argument  set  to
20       CURL_SOCKET_TIMEOUT, or call curl_multi_perform(3) if you are using the
21       simpler and older multi interface approach.
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23       The timeout value returned in the long timeout points to, is in  number
24       of milliseconds at this moment. If 0, it means you should proceed imme‐
25       diately without waiting for anything. If  it  returns  -1,  there's  no
26       timeout at all set.
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28       An application that uses the multi_socket API SHOULD NOT use this func‐
29       tion, but SHOULD instead use the CURLMOPT_TIMERFUNCTION(3)  option  for
30       proper and desired behavior.
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32       Note:  if libcurl returns a -1 timeout here, it just means that libcurl
33       currently has no stored timeout value. You must not wait too long (more
34       than a few seconds perhaps) before you call curl_multi_perform() again.
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EXAMPLE

37       struct timeval timeout;
38       long timeo;
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40       curl_multi_timeout(multi_handle, &timeo);
41       if(timeo < 0)
42         /* no set timeout, use a default */
43         timeo = 980;
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45       timeout.tv_sec = timeo / 1000;
46       timeout.tv_usec = (timeo % 1000) * 1000;
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48       /* wait for activities no longer than the set timeout */
49       select(maxfd+1, &fdread, &fdwrite, &fdexcep, &timeout);
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TYPICAL USAGE

52       Call curl_multi_timeout(3), then wait for action on the sockets. Figure
53       out which sockets to wait for by calling curl_multi_fdset(3).
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55       When there is activity or timeout, call curl_multi_perform(3) and  then
56       loop - until all transfers are complete.
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AVAILABILITY

59       This function was added in libcurl 7.15.4.
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RETURN VALUE

62       The standard CURLMcode for multi interface error codes.
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