curl/docs/libcurl/opts/CURLOPT_READDATA.3

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.TH CURLOPT_READDATA 3 "16 Jun 2014" libcurl libcurl
.SH NAME
CURLOPT_READDATA \- pointer passed to the read callback
.SH SYNOPSIS
.nf
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_READDATA, void *pointer);
.fi
.SH DESCRIPTION
Data \fIpointer\fP to pass to the file read function. If you use the
\fICURLOPT_READFUNCTION(3)\fP option, this is the pointer you get as input in
the fourth argument to the callback.

If you do not specify a read callback but instead rely on the default internal
read function, this data must be a valid readable FILE * (cast to 'void *').

If you are using libcurl as a DLL on Windows, you must use the
\fICURLOPT_READFUNCTION(3)\fP callback if you set this option, otherwise you
might experience crashes.
.SH DEFAULT
By default, this is a FILE * to stdin.
.SH PROTOCOLS
This is used for all protocols when sending data.
.SH EXAMPLE
.nf
CURL *curl = curl_easy_init();
struct MyData this;
if(curl) {
  curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");

  /* pass pointer that gets passed in to the
     CURLOPT_READFUNCTION callback */
  curl_easy_setopt(curl, CURLOPT_READDATA, &this);

  curl_easy_perform(curl);
}
.fi
.SH AVAILABILITY
This option was once known by the older name CURLOPT_INFILE, the name
\fICURLOPT_READDATA(3)\fP was introduced in 7.9.7.
.SH RETURN VALUE
This returns CURLE_OK.
.SH "SEE ALSO"
.BR CURLOPT_HEADERDATA (3),
.BR CURLOPT_READFUNCTION (3),
.BR CURLOPT_WRITEDATA (3),
.BR CURLOPT_WRITEFUNCTION (3)