CURLOPT_DEBUGDATA(3) Library Functions Manual CURLOPT_DEBUGDATA(3)

CURLOPT_DEBUGDATA - pointer passed to the debug callback

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

Pass a pointer to whatever you want passed in to your CURLOPT_DEBUGFUNCTION(3) in the last void * argument. This pointer is not used by libcurl, it is only passed to the callback.

NULL

All

struct data {

void *custom; }; static int my_trace(CURL *handle, curl_infotype type,
char *data, size_t size,
void *clientp) {
struct data *mine = clientp;
printf("our ptr: %p\n", mine->custom);
/* output debug info */ } int main(void) {
CURL *curl;
CURLcode res;
struct data my_tracedata;
curl = curl_easy_init();
if(curl) {
curl_easy_setopt(curl, CURLOPT_DEBUGFUNCTION, my_trace);
curl_easy_setopt(curl, CURLOPT_DEBUGDATA, &my_tracedata);
/* the DEBUGFUNCTION has no effect until we enable VERBOSE */
curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
res = curl_easy_perform(curl);
/* always cleanup */
curl_easy_cleanup(curl);
}
return 0; }

Always

Returns CURLE_OK

CURLOPT_DEBUGFUNCTION(3), CURLOPT_STDERR(3)

September 26, 2023 ibcurl 8.4.0