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23 .TH CURLOPT_WRITEDATA 3 "February 03, 2016" "libcurl 7.59.0" "curl_easy_setopt options"
26 CURLOPT_WRITEDATA \- custom pointer passed to the write callback
28 #include <curl/curl.h>
30 CURLcode curl_easy_setopt(CURL *handle, CURLOPT_WRITEDATA, void *pointer);
32 A data \fIpointer\fP to pass to the write callback. If you use the
33 \fICURLOPT_WRITEFUNCTION(3)\fP option, this is the pointer you'll get in that
34 callback's 4th argument. If you don't use a write callback, you must make
35 \fIpointer\fP a 'FILE *' (cast to 'void *') as libcurl will pass this to
36 \fIfwrite(3)\fP when writing data.
38 The internal \fICURLOPT_WRITEFUNCTION(3)\fP will write the data to the FILE *
39 given with this option, or to stdout if this option hasn't been set.
41 If you're using libcurl as a win32 DLL, you \fBMUST\fP use the
42 \fICURLOPT_WRITEFUNCTION(3)\fP if you set this option or you will experience
45 By default, this is a FILE * to stdout.
47 Used for all protocols.
49 A common technique is to use the write callback to store the incoming data
50 into a dynamically growing allocated buffer, and then this
51 \fICURLOPT_WRITEDATA(3)\fP is used to point to a struct or the buffer to store
52 data in. Like in the getinmemory example:
53 https://curl.haxx.se/libcurl/c/getinmemory.html
55 Available in all libcurl versions. This option was formerly known as
56 \fICURLOPT_FILE\fP, the name \fICURLOPT_WRITEDATA(3)\fP was introduced in
59 This will return CURLE_OK.
61 .BR CURLOPT_WRITEFUNCTION "(3), " CURLOPT_READDATA "(3), "