curl_easy_perform(3) Library Functions Manual curl_easy_perform(3)
NAME
curl_easy_perform - perform a blocking network transfer
SYNOPSIS
#include <curl/curl.h>
CURLcode curl_easy_perform(CURL *easy_handle);
DESCRIPTION
curl_easy_perform(3) performs a network transfer in a blocking manner
and returns when done, or earlier if it fails. For non-blocking
behavior, see curl_multi_perform(3).
Invoke this function after curl_easy_init(3) and all the
curl_easy_setopt(3) calls are made, and it performs the transfer as
described in the options. It must be called with the same easy_handle
as input as the curl_easy_init(3) call returned.
You can do any amount of calls to curl_easy_perform(3) while using the
same easy_handle. If you intend to transfer more than one file, you are
even encouraged to do so. libcurl attempts to reuse existing
connections for the following transfers, thus making the operations
faster, less CPU intense and using less network resources. You probably
want to use curl_easy_setopt(3) between the invokes to set options for
the following curl_easy_perform(3) call.
You must never call this function simultaneously from two places using
the same easy_handle. Let the function return first before invoking it
another time. If you want parallel transfers, you must use several curl
easy_handles.
A network transfer moves data to a peer or from a peer. An application
tells libcurl how to receive data by setting the
CURLOPT_WRITEFUNCTION(3) and CURLOPT_WRITEDATA(3) options. To tell
libcurl what data to send, there are a few more alternatives but two
common ones are CURLOPT_READFUNCTION(3) and CURLOPT_POSTFIELDS(3).
While the easy_handle is added to a multi handle, it cannot be used by
curl_easy_perform(3).
PROTOCOLS
This functionality affects all supported protocols
EXAMPLE
int main(void)
{
CURL *curl = curl_easy_init();
if(curl) {
CURLcode res;
curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
res = curl_easy_perform(curl);
curl_easy_cleanup(curl);
}
}
AVAILABILITY
Added in curl 7.1
RETURN VALUE
CURLE_OK (0) means everything was OK, non-zero means an error occurred
as <curl/curl.h> defines - see libcurl-errors(3). If the
CURLOPT_ERRORBUFFER(3) was set with curl_easy_setopt(3) there is a
readable error message stored in the error buffer when non-zero is
returned.
SEE ALSO
curl_easy_init(3), curl_easy_setopt(3), curl_multi_add_handle(3),
curl_multi_perform(3), libcurl-errors(3)
libcurl 2024-08-05 curl_easy_perform(3)
curl 8.9.1 - Generated Tue Aug 6 14:42:17 CDT 2024