I'm trying to compile this code in Codeblocks 16.01 on Ubuntu but it returns error message with undefined reference to 'curl_easy_init'.
But when I run in terminal gcc -L/usr/lib/x86_64-linux-gnu main.c -o curl -lcurl doesn't return any errors. 
How can I fix this?
#include <stdio.h>
#include <curl/curl.h>
void fileUpload()
{
    CURL *curl;
    CURLcode res;
    curl = curl_easy_init();
    if(curl) {
        curl_easy_setopt(curl, CURLOPT_URL,"http://test1:test1@www.idehn.tec.ac.cr/geoserver/rest/layers.xml");
        /* example.com is redirected, so we tell libcurl to follow redirection */
        curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1L);
        /* Perform the request, res will get the return code */
        res = curl_easy_perform(curl);
        /* Check for errors */
        if(res != CURLE_OK)
            fprintf(stderr, "curl_easy_perform() failed: %s\n",
                    curl_easy_strerror(res));
        FILE* file = fopen( "layers.txt", "w");
        curl_easy_setopt( curl, CURLOPT_WRITEDATA, file) ;
        /* Perform the request, res will get the return code */
        res = curl_easy_perform(curl);
        /* Check for errors */
        if(res != CURLE_OK)
            fprintf(stderr, "curl_easy_perform() failed: %s\n",
                    curl_easy_strerror(res));
        /* always cleanup */
        curl_easy_cleanup(curl);
        fclose(file);
    }
}
int main() {
    //Call to the method that charge the url content to a file with all the layers.
    fileUpload();
    return 0;
}
 
    