1--- 2c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al. 3SPDX-License-Identifier: curl 4Title: CURLOPT_WRITEDATA 5Section: 3 6Source: libcurl 7See-also: 8 - CURLOPT_HEADERDATA (3) 9 - CURLOPT_READDATA (3) 10 - CURLOPT_WRITEFUNCTION (3) 11Protocol: 12 - All 13Added-in: 7.9.7 14--- 15 16# NAME 17 18CURLOPT_WRITEDATA - pointer passed to the write callback 19 20# SYNOPSIS 21 22~~~c 23#include <curl/curl.h> 24 25CURLcode curl_easy_setopt(CURL *handle, CURLOPT_WRITEDATA, void *pointer); 26~~~ 27 28# DESCRIPTION 29 30A data *pointer* to pass to the write callback. If you use the 31CURLOPT_WRITEFUNCTION(3) option, this is the pointer you get in that 32callback's fourth and last argument. If you do not use a write callback, you 33must make *pointer* a 'FILE *' (cast to 'void *') as libcurl passes this 34to *fwrite(3)* when writing data. 35 36The internal CURLOPT_WRITEFUNCTION(3) writes the data to the FILE * 37given with this option, or to stdout if this option has not been set. 38 39If you are using libcurl as a Windows DLL, you **MUST** use a 40CURLOPT_WRITEFUNCTION(3) if you set this option or you might experience 41crashes. 42 43# DEFAULT 44 45stdout 46 47# %PROTOCOLS% 48 49# EXAMPLE 50 51A common technique is to use the write callback to store the incoming data 52into a dynamically growing allocated buffer, and then this 53CURLOPT_WRITEDATA(3) is used to point to a struct or the buffer to store data 54in. Like in the getinmemory example: 55https://curl.se/libcurl/c/getinmemory.html 56 57# HISTORY 58 59This option was formerly known as CURLOPT_FILE, the name CURLOPT_WRITEDATA(3) 60was added in 7.9.7. 61 62# %AVAILABILITY% 63 64# RETURN VALUE 65 66This returns CURLE_OK. 67
