curl/docs/libcurl/opts/CURLOPT_DEBUGDATA.md
Daniel Stenberg e3fe020089
docs/libcurl: generate PROTOCOLS from meta-data
Remove the PROTOCOLS section from the source files completely and
instead generate them based on the header data in the curldown files.

It also generates TLS backend information for options marked for TLS as
protocol.

Closes #13175
2024-03-23 18:13:03 +01:00

85 lines
1.5 KiB
Markdown

---
c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
SPDX-License-Identifier: curl
Title: CURLOPT_DEBUGDATA
Section: 3
Source: libcurl
See-also:
- CURLOPT_DEBUGFUNCTION (3)
- CURLOPT_STDERR (3)
Protocol:
- All
---
# NAME
CURLOPT_DEBUGDATA - pointer passed to the debug callback
# SYNOPSIS
~~~c
#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
# EXAMPLE
~~~c
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
Always
# RETURN VALUE
Returns CURLE_OK