main.c

#include <curl/curl.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>

size_t write_data(void *ptr, size_t size, size_t nmemb, FILE *stream) {
	size_t written = fwrite(ptr, size, nmemb, stream);
	return written;
}

void random_string(char * string, size_t length)
{

	char chars[62] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
			 "abcdefghijklmnopqrstuvwxyz"
			 "1234567890";

	unsigned int num_chars = (unsigned int) length;
	unsigned int i;
	for (i = 0; i < num_chars; ++i)
	{
		string[i] = chars[rand()%62];
	}

	string[num_chars] = '\0';
}


int main() {
	srand((unsigned int) time(0));

	CURL* curl;
	CURLcode res;
	FILE *fp;

	char* urlbegin = "http://i.imgur.com/";
	char* ext = ".png";
	char url_array[5];
	char* url_pointer;

	char* out = "out.png";

	random_string(url_array, 5);
	url_pointer=&url_array[0];

	char* url;
	url = malloc(strlen(urlbegin)+1+9);
	strcpy(url, urlbegin);
	strcat(url, url_pointer);
	strcat(url, ".png");

//	printf("%s\n", url);

	curl = curl_easy_init();

	struct stat st;

	if (curl)
	{
		fp = fopen(out, "wb");
		curl_easy_setopt(curl, CURLOPT_URL, url);
		curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_data);
		curl_easy_setopt(curl, CURLOPT_WRITEDATA, fp);
		res = curl_easy_perform(curl);
		curl_easy_cleanup(curl);

		stat(out, &st);
		if (st.st_size < 1) { printf("Searching...\n"); main(); }
		else { printf("Found Image: %s\n", url); }

		fclose(fp);
	}
  return 0;
}