CURLINFO_CONTENT_TYPE - Man Page

#include <curl/curl.h>

CURLcode curl_easy_getinfo(CURL *handle, CURLINFO_CONTENT_TYPE, char **ct);

Pass a pointer to a char pointer to receive the content-type of the downloaded object. This is the value read from the Content-Type: field. If you get NULL, it means that the server did not send a valid Content-Type header or that the protocol used does not support this.

The ct pointer is set to NULL or pointing to private memory. You MUST NOT free it - it gets freed when you call curl_easy_cleanup(3) on the corresponding curl handle.

The modern way to get this header from a response is to instead use the curl_easy_header(3) function.

This functionality affects http only

int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    CURLcode res;
    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");

    res = curl_easy_perform(curl);

    if(!res) {
      /* extract the content-type */
      char *ct = NULL;
      res = curl_easy_getinfo(curl, CURLINFO_CONTENT_TYPE, &ct);
      if(!res && ct) {
        printf("Content-Type: %s\n", ct);
      }
    }
    curl_easy_cleanup(curl);
  }
}

Added in curl 7.9.4

curl_easy_getinfo(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).

CURLOPT_HEADERFUNCTION(3), curl_easy_getinfo(3), curl_easy_header(3), curl_easy_setopt(3)

curl_easy_getinfo(3), curl_easy_header(3).