CURLOPT_WRITEDATA - Man Page

#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_WRITEDATA, void *pointer);

A data pointer to pass to the write callback. If you use the CURLOPT_WRITEFUNCTION(3) option, this is the pointer you will get in that callback's fourth and last argument. If you do not use a write callback, you must make pointer a 'FILE *' (cast to 'void *') as libcurl will pass this to fwrite(3) when writing data.

The internal CURLOPT_WRITEFUNCTION(3) will write the data to the FILE * given with this option, or to stdout if this option has not been set.

If you are using libcurl as a win32 DLL, you MUST use a CURLOPT_WRITEFUNCTION(3) if you set this option or you will experience crashes.

By default, this is a FILE * to stdout.

Used for all protocols.

A common technique is to use the write callback to store the incoming data into a dynamically growing allocated buffer, and then this CURLOPT_WRITEDATA(3) is used to point to a struct or the buffer to store data in. Like in the getinmemory example: https://curl.se/libcurl/c/getinmemory.html

Available in all libcurl versions. This option was formerly known as CURLOPT_FILE, the name CURLOPT_WRITEDATA(3) was introduced in 7.9.7.

This will return CURLE_OK.

CURLOPT_WRITEFUNCTION(3), CURLOPT_READDATA(3),

curl_easy_perform(3), curl_easy_setopt(3), CURLOPT_READDATA(3), CURLOPT_WRITEFUNCTION(3), libcurl-tutorial(3).