docs/libcurl/opts/CURLOPT_DEBUGDATA.md
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
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 */
return 0;
}
int main(void)
{
CURL *curl;
CURLcode result;
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/");
result = curl_easy_perform(curl);
/* always cleanup */
curl_easy_cleanup(curl);
}
return 0;
}
curl_easy_setopt(3) returns a CURLcode indicating success or error.
CURLE_OK (0) means everything was OK, non-zero means an error occurred, see libcurl-errors(3).