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.TH CURLOPT_TRAILERDATA 3 "14 Aug 2018" libcurl libcurl
.SH NAME
CURLOPT_TRAILERDATA \- pointer passed to trailing headers callback
.SH SYNOPSIS
.nf
#include <curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_TRAILERDATA, void *userdata);
.fi
.SH DESCRIPTION
Data pointer to be passed to the HTTP trailer callback function.
.SH DEFAULT
NULL
.SH PROTOCOLS
HTTP
.SH EXAMPLE
.nf
struct MyData {
  void *custom;
};

int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    struct MyData data;
    curl_easy_setopt(curl, CURLOPT_TRAILERDATA, &data);
  }
}
.fi

A more complete example can be found in examples/http_trailers.html
.SH AVAILABILITY
This option was added in curl 7.64.0 and is present if HTTP support is enabled
.SH RETURN VALUE
Returns CURLE_OK.
.SH "SEE ALSO"
.BR CURLOPT_TRAILERFUNCTION (3),
.BR CURLOPT_WRITEFUNCTION (3)