curl_easy_perform(3) | libcurl Manual | curl_easy_perform(3) |
curl_easy_perform - perform a blocking file transfer
#include <curl/curl.h>
CURLcode curl_easy_perform(CURL *easy_handle);
Invoke this function after curl_easy_init(3) and all the curl_easy_setopt(3) calls are made, and will perform 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.
curl_easy_perform(3) performs the entire request in a blocking manner and returns when done, or if it failed. For non-blocking behavior, see curl_multi_perform(3).
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 will then attempt to re-use the same connection for the following transfers, thus making the operations faster, less CPU intense and using less network resources. Just note that you will have to use curl_easy_setopt(3) between the invokes to set options for the following curl_easy_perform.
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.
While the easy_handle is added to a multi handle, it cannot be used by curl_easy_perform(3).
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 will be a readable error message in the error buffer when non-zero is returned.
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); }
curl_easy_init(3), curl_easy_setopt(3), curl_multi_add_handle(3), curl_multi_perform(3), libcurl-errors(3),
November 4, 2020 | libcurl 7.74.0 |