CURLINFO_CONDITION_UNMET explained

Name

CURLINFO_CONDITION_UNMET - get info on unmet time conditional or 304 HTTP response.

Synopsis

#include <curl/curl.h>
 
CURLcode curl_easy_getinfo(CURL *handle, CURLINFO_CONDITION_UNMET,
                           long *unmet);

Description

Pass a pointer to a long to receive the number 1 if the condition provided in the previous request did not match (see CURLOPT_TIMECONDITION). Alas, if this returns a 1 you know that the reason you did not get data in return is because it did not fulfill the condition. The long this argument points to will get a zero stored if the condition instead was met. This can also return 1 if the server responded with a 304 HTTP status code, for example after sending a custom "If-Match-*" header.

Protocols

HTTP and some

Example

CURL *curl = curl_easy_init();
if(curl) {
  curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
 
  /* January 1, 2020 is 1577833200 */
  curl_easy_setopt(curl, CURLOPT_TIMEVALUE, 1577833200L);
 
  /* If-Modified-Since the above time stamp */
  curl_easy_setopt(curl, CURLOPT_TIMECONDITION,
                   (long)CURL_TIMECOND_IFMODSINCE);
 
  /* Perform the request */
  res = curl_easy_perform(curl);
 
  if(!res) {
    /* check the time condition */
    long unmet;
    res = curl_easy_getinfo(curl, CURLINFO_CONDITION_UNMET, &unmet);
    if(!res) {
      printf("The time condition was %sfulfilled\n", unmet?"NOT":"");
    }
  }
}

Availability

Added in 7.19.4

Return value

Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.