CURLOPT_UPLOAD_BUFFERSIZE(3)

1CURLOPT_UPLOAD_BUFFERSIZE(3)curl_easy_setopt optionsCURLOPT_UPLOAD_BUFFERSIZE(3)
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NAME

6       CURLOPT_UPLOAD_BUFFERSIZE - upload buffer size
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SYNOPSIS

9       #include <curl/curl.h>
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11       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_UPLOAD_BUFFERSIZE, long size);
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DESCRIPTION

14       Pass  a  long  specifying your preferred size (in bytes) for the upload
15       buffer in libcurl. It makes libcurl uses  a  larger  buffer  that  gets
16       passed  to  the next layer in the stack to get sent off. In some setups
17       and for some protocols, there's a huge performance benefit of having  a
18       larger upload buffer.
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20       This  is just treated as a request, not an order. You cannot be guaran‐
21       teed to actually get the given size.
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23       The upload buffer size is by default 64 kilobytes. The  maximum  buffer
24       size  allowed to be set is 2 megabytes. The minimum buffer size allowed
25       to be set is 16 kilobytes.
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27       Since curl 7.61.1 the upload buffer is allocated on-demand - so if  the
28       handle  is  not  used  for upload, this buffer will not be allocated at
29       all.
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31       DO NOT set this option on a handle that is currently used for an active
32       transfer as that may lead to unintended consequences.
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DEFAULT

35       65536 bytes
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PROTOCOLS

38       All
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EXAMPLE

41       CURL *curl = curl_easy_init();
42       if(curl) {
43         curl_easy_setopt(curl, CURLOPT_URL, "sftp://example.com/foo.bin");
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45         /* ask libcurl to allocate a larger upload buffer */
46         curl_easy_setopt(curl, CURLOPT_UPLOAD_BUFFERSIZE, 120000L);
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48         ret = curl_easy_perform(curl);
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50         curl_easy_cleanup(curl);
51       }
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AVAILABILITY

54       Added in 7.62.0.
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RETURN VALUE

57       Returns  CURLE_OK  if the option is supported, and CURLE_UNKNOWN_OPTION
58       if not.
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