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Updated: Thursday, June 13, 2019
 
 

CURLOPT_UPKEEP_INTERVAL_MS (3)

Name

CURLOPT_UPKEEP_INTERVAL_MS - connection upkeep interval

Synopsis

#include <curl/curl.h>

CURLcode   curl_easy_setopt(CURL  *handle,  CURLOPT_UPKEEP_INTERVAL_MS,
long upkeep_interval_ms);

Description

curl_easy_setopt options                         CURLOPT_UPKEEP_INTERVAL_MS(3)



NAME
       CURLOPT_UPKEEP_INTERVAL_MS - connection upkeep interval

SYNOPSIS
       #include <curl/curl.h>

       CURLcode   curl_easy_setopt(CURL  *handle,  CURLOPT_UPKEEP_INTERVAL_MS,
       long upkeep_interval_ms);

DESCRIPTION
       Some protocols have "connection upkeep"  mechanisms.  These  mechanisms
       usually send some traffic on existing connections in order to keep them
       alive; this can prevent connections from being closed due to  overzeal-
       ous firewalls, for example.

       The  user needs to explicitly call curl_easy_upkeep(3) in order to per-
       form the upkeep work.

       Currently the only protocol  with  a  connection  upkeep  mechanism  is
       HTTP/2:   when   the   connection   upkeep  interval  is  exceeded  and
       curl_easy_upkeep(3) is called, an HTTP/2 PING frame is sent on the con-
       nection.


DEFAULT
       CURL_UPKEEP_INTERVAL_DEFAULT  (currently defined as 60000L, which is 60
       seconds)

EXAMPLE
       CURL *curl = curl_easy_init();
       if(curl) {
         /* Make a connection to an HTTP/2 server. */
         curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");

         /* Set the interval to 30000ms / 30s */
         curl_easy_setopt(curl, CURLOPT_UPKEEP_INTERVAL_MS, 30000L);

         curl_easy_perform(curl);

         /* Perform more work here. */

         /* While the connection is being held open, curl_easy_upkeep() can be
            called. If curl_easy_upkeep() is called and the time since the last
            upkeep exceeds the interval, then an HTTP/2 PING is sent. */
         curl_easy_upkeep(curl);

         /* Perform more work here. */

         /* always cleanup */
         curl_easy_cleanup(curl);
       }

AVAILABILITY
       Added in 7.62.0

RETURN VALUE
       Returns CURLE_OK



ATTRIBUTES
       See attributes(7) for descriptions of the following attributes:


       +---------------+------------------+
       |ATTRIBUTE TYPE | ATTRIBUTE VALUE  |
       +---------------+------------------+
       |Availability   | web/curl         |
       +---------------+------------------+
       |Stability      | Uncommitted      |
       +---------------+------------------+
NOTES
       This    software    was    built    from    source     available     at
       https://github.com/oracle/solaris-userland.    The  original  community
       source   was    downloaded    from     https://github.com/curl/curl/ar-
       chive/curl-7_64_0.zip

       Further information about this software can be found on the open source
       community website at http://curl.haxx.se/.



libcurl 7.62.0                    31 Oct 2018
                                                 CURLOPT_UPKEEP_INTERVAL_MS(3)