CURLOPT_WRITEDATA(3) Library Functions Manual CURLOPT_WRITEDATA(3)
NAME
CURLOPT_WRITEDATA - pointer passed to the write callback
SYNOPSIS
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_WRITEDATA, void *pointer);
DESCRIPTION
A data pointer to pass to the write callback. If you use the
CURLOPT_WRITEFUNCTION(3) option, this is the pointer you 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
passes this to fwrite(3) when writing data.
The internal CURLOPT_WRITEFUNCTION(3) writes 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 Windows DLL, you MUST use a
CURLOPT_WRITEFUNCTION(3) if you set this option or you might experience
crashes.
DEFAULT
stdout
PROTOCOLS
This functionality affects all supported protocols
EXAMPLE
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
HISTORY
This option was formerly known as CURLOPT_FILE, the name
CURLOPT_WRITEDATA(3) was added in 7.9.7.
AVAILABILITY
Added in curl 7.9.7
RETURN VALUE
This returns CURLE_OK.
SEE ALSO
CURLOPT_HEADERDATA(3), CURLOPT_READDATA(3), CURLOPT_WRITEFUNCTION(3)
libcurl 2025-04-16 CURLOPT_WRITEDATA(3)
curl 8.13.0 - Generated Wed May 7 16:39:54 CDT 2025