Hello All,

I am trying to download a non-existent file from a repository by giving the URL, using curl APIs. It is throwing an error message "The requested URL returned error: 404" but the specified file is downloaded with 0 bytes. My code snippet is as follows :


#include <curl/curl.h>
#include <stdio.h>
#include <math.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <stdlib.h>

static char errorBuffer[CURL_ERROR_SIZE];
size_t D_Write(void *ptr,size_t size, size_t nmemb, FILE *stream)
{
size_t ret;
ret = fwrite(ptr, size, nmemb*size, stream);
return ret;
}
int Download(const char *f_name, const char *p_url)
{
CURLcode ret;
CURL *hnd = curl_easy_init();
FILE *f_ptr = fopen(f_name, "wb");
curl_easy_setopt(hnd, CURLOPT_WRITEDATA,f_ptr);
curl_easy_setopt(hnd, CURLOPT_WRITEFUNCTION,D_Write );
curl_easy_setopt(hnd, CURLOPT_INFILESIZE_LARGE, (curl_off_t)-1);
curl_easy_setopt(hnd, CURLOPT_URL, p_url);
curl_easy_setopt(hnd, CURLOPT_PROXY, NULL);
curl_easy_setopt(hnd, CURLOPT_NOPROGRESS, 0);
curl_easy_setopt(hnd, CURLOPT_HEADER, 0);
curl_easy_setopt(hnd, CURLOPT_FAILONERROR, 1);
curl_easy_setopt(hnd, CURLOPT_UPLOAD, 0);
curl_easy_setopt(hnd, CURLOPT_DIRLISTONLY, 0);
curl_easy_setopt(hnd, CURLOPT_APPEND, 0);
curl_easy_setopt(hnd, CURLOPT_NETRC, 0);
curl_easy_setopt(hnd, CURLOPT_FOLLOWLOCATION, 0);
curl_easy_setopt(hnd, CURLOPT_UNRESTRICTED_AUTH, 0);
curl_easy_setopt(hnd, CURLOPT_TRANSFERTEXT, 0);
curl_easy_setopt(hnd, CURLOPT_USERPWD, NULL);
curl_easy_setopt(hnd, CURLOPT_PROXYUSERPWD, NULL);
curl_easy_setopt(hnd, CURLOPT_NOPROXY, NULL);
curl_easy_setopt(hnd, CURLOPT_RANGE, NULL);
curl_easy_setopt(hnd, CURLOPT_ERRORBUFFER, errorBuffer);
curl_easy_setopt(hnd, CURLOPT_TIMEOUT, 0);
curl_easy_setopt(hnd, CURLOPT_REFERER, NULL);
curl_easy_setopt(hnd, CURLOPT_AUTOREFERER, 0);
curl_easy_setopt(hnd, CURLOPT_USERAGENT, "curl/7.19.7 (i486-pc-linux-gnu) libcurl/7.19.7 OpenSSL/0.9.8k zlib/1.2.3.3 libidn/1.15");
curl_easy_setopt(hnd, CURLOPT_FTPPORT, NULL);
curl_easy_setopt(hnd, CURLOPT_LOW_SPEED_LIMIT, 0);
curl_easy_setopt(hnd, CURLOPT_LOW_SPEED_TIME, 0);
curl_easy_setopt(hnd, CURLOPT_MAX_SEND_SPEED_LARGE, (curl_off_t)0);
curl_easy_setopt(hnd, CURLOPT_MAX_RECV_SPEED_LARGE, (curl_off_t)0);
curl_easy_setopt(hnd, CURLOPT_RESUME_FROM_LARGE, (curl_off_t)0);
curl_easy_setopt(hnd, CURLOPT_COOKIE, NULL);
curl_easy_setopt(hnd, CURLOPT_HTTPHEADER, NULL);
curl_easy_setopt(hnd, CURLOPT_SSLCERT, NULL);
curl_easy_setopt(hnd, CURLOPT_SSLCERTTYPE, NULL);
curl_easy_setopt(hnd, CURLOPT_SSLKEY, NULL);
curl_easy_setopt(hnd, CURLOPT_SSLKEYTYPE, NULL);
curl_easy_setopt(hnd, CURLOPT_KEYPASSWD, NULL);
curl_easy_setopt(hnd, CURLOPT_SSH_PRIVATE_KEYFILE, NULL);
curl_easy_setopt(hnd, CURLOPT_SSH_PUBLIC_KEYFILE, NULL);
curl_easy_setopt(hnd, CURLOPT_SSH_HOST_PUBLIC_KEY_MD5, NULL);
curl_easy_setopt(hnd, CURLOPT_SSL_VERIFYHOST, 2);
curl_easy_setopt(hnd, CURLOPT_MAXREDIRS, 50);
curl_easy_setopt(hnd, CURLOPT_CRLF, 0);
curl_easy_setopt(hnd, CURLOPT_QUOTE, NULL);
curl_easy_setopt(hnd, CURLOPT_POSTQUOTE, NULL);
curl_easy_setopt(hnd, CURLOPT_PREQUOTE, NULL);
curl_easy_setopt(hnd, CURLOPT_WRITEHEADER, NULL);
curl_easy_setopt(hnd, CURLOPT_COOKIEFILE, NULL);
curl_easy_setopt(hnd, CURLOPT_COOKIESESSION, 0);
curl_easy_setopt(hnd, CURLOPT_SSLVERSION, 0);
curl_easy_setopt(hnd, CURLOPT_TIMECONDITION, 0);
curl_easy_setopt(hnd, CURLOPT_TIMEVALUE, 0);
curl_easy_setopt(hnd, CURLOPT_CUSTOMREQUEST, NULL);
//curl_easy_setopt(hnd, CURLOPT_STDERR, errorBuffer);
curl_easy_setopt(hnd, CURLOPT_HTTPPROXYTUNNEL, 0);
/*curl_easy_setopt(hnd, CURLOPT_INTERFACE, NULL);
curl_easy_setopt(hnd, CURLOPT_KRBLEVEL, NULL);
curl_easy_setopt(hnd, CURLOPT_TELNETOPTIONS, NULL);
curl_easy_setopt(hnd, CURLOPT_RANDOM_FILE, NULL);
curl_easy_setopt(hnd, CURLOPT_EGDSOCKET, NULL);*/
curl_easy_setopt(hnd, CURLOPT_CONNECTTIMEOUT, 3);
/* curl_easy_setopt(hnd, CURLOPT_DEBUGFUNCTION, 0x804db80); [REMARK] */
/* curl_easy_setopt(hnd, CURLOPT_DEBUGDATA, 0xbf81fb44); [REMARK] */
curl_easy_setopt(hnd, CURLOPT_VERBOSE, 1);
curl_easy_setopt(hnd, CURLOPT_ENCODING, NULL);
/*curl_easy_setopt(hnd, CURLOPT_FTP_CREATE_MISSING_DIRS, 0);
curl_easy_setopt(hnd, CURLOPT_IPRESOLVE, 0);
curl_easy_setopt(hnd, CURLOPT_FTP_ACCOUNT, NULL);
curl_easy_setopt(hnd, CURLOPT_IGNORE_CONTENT_LENGTH, 0);
curl_easy_setopt(hnd, CURLOPT_FTP_SKIP_PASV_IP, 0);
curl_easy_setopt(hnd, CURLOPT_FTP_FILEMETHOD, 0);
curl_easy_setopt(hnd, CURLOPT_FTP_ALTERNATIVE_TO_USER, NULL);*/
curl_easy_setopt(hnd, CURLOPT_SSL_SESSIONID_CACHE, 1);
/* curl_easy_setopt(hnd, CURLOPT_SOCKOPTFUNCTION, 0x804da50); [REMARK] */
/* curl_easy_setopt(hnd, CURLOPT_SOCKOPTDATA, 0xbf81fb44); [REMARK] */
curl_easy_setopt(hnd, CURLOPT_POSTREDIR, 0);

ret = curl_easy_perform(hnd);

curl_easy_cleanup(hnd);
fclose(f_ptr);
if (ret == CURLE_OK)
{
exit(0);
}
else
{
printf( "Error: %d - %s \n",ret, errorBuffer);
exit(-1);
}
return (int)ret;
}


int main()
{
Download( "file name", "specified url" ) ;
return 0;
}

This is giving output as

% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
0 0 0 0 0 0 0 0 --:--:-- --:--:-- --:--:-- 0* The requested URL returned error: 404
0 0 0 0 0 0 0 0 --:--:-- --:--:-- --:--:-- 0* Closing connection #0

Error: 22 - The requested URL returned error: 404

And its creating a file of 0 bytes with the specified file name. This should not happen. File should not be created. How to do it?

Some1 plz help. Thanks in advance.

Please put your code inside code tags, like this:
Curl isn't creating the file, it's getting created at the call to fopen.

Hi ntubski,

Then plz tell me how can i put a restriction in creating the file, when curl will return the error message.

I'm not sure what you mean by "put a restriction", but if you don't want an empty file to be created, just don't fopen the file until you get the first chunk of bytes.

1 members found this post helpful.

please tell me where to put fopen in my code.

The file is being created because of the fopen(). The position of the call to fopen() that you have placed in your code is fine; but what you are neglecting to do at the moment is to fully handle the error from libcurl.

Do something like this:

I was thinking more along the lines of:

Messed that up, see post #9 instead.

Huh?

Please look at the code you posted; while at it, peruse the man-page for fwrite().

I got my parameters backwards.

thnx dwhitney, unlink worked for me.