curl / libcurl / API / curl_easy_setopt / CURLOPT_READDATA

CURLOPT_READDATA explained

Name

CURLOPT_READDATA - pointer passed to the read callback

Synopsis

 #include <curl/curl.h>   CURLcode curl_easy_setopt(CURL *handle, CURLOPT_READDATA, void *pointer);

Description

Data pointer to pass to the file read function. If you use the CURLOPT_READFUNCTION option, this is the pointer you get as input in the fourth argument to the callback.

If you do not specify a read callback but instead rely on the default internal read function, this data must be a valid readable FILE * (cast to 'void *').

If you are using libcurl as a DLL on Windows, you must use the CURLOPT_READFUNCTION callback if you set this option, otherwise you might experience crashes.

Default

stdin

Protocols

This functionality affects all supported protocols

Example

 struct MyData {   void *custom; };   int main(void) {   CURL *curl = curl_easy_init();   struct MyData this;   if(curl) {   curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");     /* pass pointer that gets passed in to the   CURLOPT_READFUNCTION callback */   curl_easy_setopt(curl, CURLOPT_READDATA, &this);     curl_easy_perform(curl);   } }

History

This option was once known by the older name CURLOPT_INFILE, the name CURLOPT_READDATA was introduced in 7.9.7.

Availability

Added in curl 7.9.7

Return value

This returns CURLE_OK.