Tribblix: manual page: CURLOPT

CURLOPT_DEBUGDATA(3) Introduction to Library Functions CURLOPT_DEBUGDATA(3)

NAME

CURLOPT_DEBUGDATA - pointer passed to the debug callback

SYNOPSIS

#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_DEBUGDATA, void *pointer);

DESCRIPTION

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.

DEFAULT

NULL

PROTOCOLS

This functionality affects all supported protocols

EXAMPLE

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;
}

AVAILABILITY

Added in curl 7.9.6

RETURN VALUE

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).