CURLOPT_VERBOSE explained

Name

CURLOPT_VERBOSE - verbose mode

Synopsis

#include <curl/curl.h>
 
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_VERBOSE, long onoff);

Description

Set the onoff parameter to 1 to make the library display a lot of verbose information about its operations on this handle. Useful for libcurl and/or protocol debugging and understanding. The verbose information is sent to stderr, or the stream set with CURLOPT_STDERR.

You hardly ever want this enabled in production use, you almost always want this used when you debug/report problems.

To also get all the protocol data sent and received, consider using the CURLOPT_DEBUGFUNCTION.

WARNING this may show sensitive contents from headers and data.

Default

0, meaning disabled.

Protocols

This functionality affects all supported protocols

Example

int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
 
    /* ask libcurl to show us the verbose output */
    curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
 
    /* Perform the request */
    curl_easy_perform(curl);
  }
}

Availability

Added in curl 7.1

Return value

curl_easy_setopt returns a CURLcode indicating success or error.

CURLE_OK (0) means everything was OK, non-zero means an error occurred, see libcurl-errors.