CURLOPT_BUFFERSIZE(3)      curl_easy_setopt options      CURLOPT_BUFFERSIZE(3)

NAME
       CURLOPT_BUFFERSIZE - set preferred receive buffer size

SYNOPSIS
       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_BUFFERSIZE, long size);

DESCRIPTION
       Pass a long specifying your preferred size (in bytes) for the receive
       buffer in libcurl.  The main point of this would be that the write
       callback gets called more often and with smaller chunks. Secondly, for
       some protocols, there's a benefit of having a larger buffer for
       performance.

       This is just treated as a request, not an order. You cannot be
       guaranteed to actually get the given size.

       This buffer size is by default CURL_MAX_WRITE_SIZE (16kB). The maximum
       buffer size allowed to be set is CURL_MAX_READ_SIZE (512kB). The
       minimum buffer size allowed to be set is 1024.

       DO NOT set this option on a handle that is currently used for an active
       transfer as that may lead to unintended consequences.

DEFAULT
       CURL_MAX_WRITE_SIZE (16kB)

PROTOCOLS
       All

EXAMPLE
       CURL *curl = curl_easy_init();
       if(curl) {
         curl_easy_setopt(curl, CURLOPT_URL, "sftp://example.com/foo.bin");

         /* ask libcurl to allocate a larger receive buffer */
         curl_easy_setopt(curl, CURLOPT_BUFFERSIZE, 120000L);

         ret = curl_easy_perform(curl);

         curl_easy_cleanup(curl);
       }

AVAILABILITY
       Added in 7.10.  Growing the buffer was added in 7.53.0.

RETURN VALUE
       Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION
       if not.

SEE ALSO
       CURLOPT_MAX_RECV_SPEED_LARGE(3), CURLOPT_WRITEFUNCTION(3),

libcurl 7.77.0                    May 6, 2021            CURLOPT_BUFFERSIZE(3)