CURLSHOPT_LOCKFUNC(3)

1CURLSHOPT_LOCKFUNC(3)           libcurl Manual           CURLSHOPT_LOCKFUNC(3)
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NAME

6       CURLSHOPT_LOCKFUNC - mutex lock callback
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SYNOPSIS

9       #include <curl/curl.h>
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11       void lockcb(CURL *handle, curl_lock_data data, curl_lock_access access,
12                   void *userptr);
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14       CURLSHcode curl_share_setopt(CURLSH *share, CURLSHOPT_LOCKFUNC, lockcb);
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DESCRIPTION

17       Set a mutex lock callback for the share object, to allow it to get used
18       by multiple threads concurrently. There's a corresponding CURLSHOPT_UN‐
19       LOCKFUNC(3) callback called when the mutex is again released.
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21       The lockcb argument must be a pointer to a function matching the proto‐
22       type shown above. The arguments to the callback are:
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24       handle is the currently active easy handle in use when the share object
25       is intended to get used.
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27       The  data  argument tells what kind of data libcurl wants to lock. Make
28       sure that the callback uses a different lock for each kind of data.
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30       access defines what access type libcurl wants, shared or single.
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32       userptr is the private pointer you set with  CURLSHOPT_USERDATA.   This
33       pointer is not used by libcurl itself.
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PROTOCOLS

36       All
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EXAMPLE

39         CURLSHcode sh
40         share = curl_share_init();
41         sh = curl_share_setopt(share, CURLSHOPT_LOCKFUNC, mutex_lock);
42         if(sh)
43           printf("Error: %s\n", curl_share_strerror(sh));
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AVAILABILITY

46       Added in 7.10
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RETURN VALUE

49       CURLSHE_OK  (zero)  means  that  the  option was set properly, non-zero
50       means an error occurred. See libcurl-errors(3) for the full  list  with
51       descriptions.
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