.\" generated by cd2nroff 0.1 from CURLOPT_TRAILERDATA.md .TH CURLOPT_TRAILERDATA 3 "March 22 2024" libcurl .SH NAME CURLOPT_TRAILERDATA \- pointer passed to trailing headers callback .SH SYNOPSIS .nf #include 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 .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)