curl/docs/libcurl/curl_easy_perform.md

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---
c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
SPDX-License-Identifier: curl
Title: curl_easy_perform
Section: 3
Source: libcurl
See-also:
- curl_easy_init (3)
- curl_easy_setopt (3)
- curl_multi_add_handle (3)
- curl_multi_perform (3)
- libcurl-errors (3)
Protocol:
- All
Added-in: 7.1
---
# NAME
curl_easy_perform - perform a blocking network transfer
# SYNOPSIS
~~~c
#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).
# EXAMPLE
~~~c
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);
}
}
~~~
# 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 CURLOPT_ERRORBUFFER(3)
was set with curl_easy_setopt(3) there is an error message stored in the error
buffer when non-zero is returned.