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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)
2024-12-11 | libcurl |