CURLOPT_UPLOAD_BUFFERSIZE - upload buffer size
#include <curl/curl.h> CURLcode curl_easy_setopt(CURL *handle, CURLOPT_UPLOAD_BUFFERSIZE, long size);
curl_easy_setopt options CURLOPT_UPLOAD_BUFFERSIZE(3)
NAME
CURLOPT_UPLOAD_BUFFERSIZE - upload buffer size
SYNOPSIS
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_UPLOAD_BUFFERSIZE, long size);
DESCRIPTION
Pass a long specifying your preferred size (in bytes) for the upload
buffer in libcurl. It makes libcurl uses a larger buffer that gets
passed to the next layer in the stack to get sent off. In some setups
and for some protocols, there's a huge performance benefit of having a
larger upload buffer.
This is just treated as a request, not an order. You cannot be guaran-
teed to actually get the given size.
The upload buffer size is by default 64 kilobytes. The maximum buffer
size allowed to be set is 2 megabytes. The minimum buffer size allowed
to be set is 16 kilobytes.
Since curl 7.61.1 the upload buffer is allocated on-demand - so if the
handle is not used for upload, this buffer will not be allocated at
all.
DO NOT set this option on a handle that is currently used for an active
transfer as that may lead to unintended consequences.
DEFAULT
64 kB
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 upload buffer */
curl_easy_setopt(curl, CURLOPT_UPLOAD_BUFFERSIZE, 120000L);
ret = curl_easy_perform(curl);
curl_easy_cleanup(curl);
}
AVAILABILITY
Added in 7.62.0.
RETURN VALUE
Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION
if not.
ATTRIBUTES
See attributes(7) for descriptions of the following attributes:
+---------------+------------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+------------------+
|Availability | web/curl |
+---------------+------------------+
|Stability | Uncommitted |
+---------------+------------------+
SEE ALSO
CURLOPT_BUFFERSIZE(3), CURLOPT_READFUNCTION(3),
NOTES
Source code for open source software components in Oracle Solaris can
be found at https://www.oracle.com/downloads/opensource/solaris-source-
code-downloads.html.
This software was built from source available at
https://github.com/oracle/solaris-userland. The original community
source was downloaded from https://curl.se/down-
load/curl-7.83.1.tar.bz2.
Further information about this software can be found on the open source
community website at http://curl.haxx.se/.
libcurl 7.83.1 November 26, 2021
CURLOPT_UPLOAD_BUFFERSIZE(3)