CURLOPT_WRITEDATA

Section: curl_easy_setopt options (3)
Updated: August 11, 2018
Page Index

 

NAME

CURLOPT_WRITEDATA - custom 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'll get in that callback's 4th argument. If you don't 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 hasn't been set.

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

DEFAULT

By default, this is a FILE * to stdout.  

PROTOCOLS

Used for all 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.haxx.se/libcurl/c/getinmemory.html  

AVAILABILITY

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

RETURN VALUE

This will return CURLE_OK.  

SEE ALSO

CURLOPT_WRITEFUNCTION(3), CURLOPT_READDATA(3),


 

Index

NAME
SYNOPSIS
DESCRIPTION
DEFAULT
PROTOCOLS
EXAMPLE
AVAILABILITY
RETURN VALUE
SEE ALSO
LinuxReviews : manual page archive : man3