DOKK / manpages / debian 12 / libcurl4-doc / CURLOPT_PREREQDATA.3.en
CURLOPT_PREREQDATA(3) curl_easy_setopt options CURLOPT_PREREQDATA(3)

CURLOPT_PREREQDATA - pointer passed to the pre-request callback

#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_PREREQDATA, void *pointer);

Pass a pointer that will be untouched by libcurl and passed as the first argument in the pre-request callback set with CURLOPT_PREREQFUNCTION(3).

NULL

All

static int prereq_callback(void *clientp,

char *conn_primary_ip,
char *conn_local_ip,
int conn_primary_port,
int conn_local_port) {
printf("Connection made to %s:%s\n", conn_primary_ip, conn_primary_port);
return CURL_PREREQFUNC_OK; } {
struct data prereq_data;
curl_easy_setopt(CURL *handle, CURLOPT_PREREQFUNCTION, prereq_callback);
curl_easy_setopt(CURL *handle, CURLOPT_PREREQDATA, &prereq_data); }

Added in 7.80.0

Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.

CURLOPT_PREREQFUNCTION(3)

January 2, 2023 libcurl 7.88.1