curl/docs/examples/post-callback.c
2002-03-14 14:53:00 +00:00

90 lines
2.5 KiB
C

/*****************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* $Id$
*
* An example source code that issues a HTTP POST and we provide the actual
* data through a read callback.
*
* Please be aware of the fact that the size of the posted data MUST be
* specified before the transfer is being made (with CURLOPT_POSTFIELDSIZE).
* This requirement will change when libcurl starts supporting chunked-encoded
* sends.
*
* This example requires libcurl 7.9.6 or later.
*/
#include <stdio.h>
#include <string.h>
#include <curl/curl.h>
#if LIBCURL_VERSION_NUM < 0x070906
#error this example source requires libcurl 7.9.6 or newer
#endif
char data[]="this is what we post to the silly web server";
struct WriteThis {
char *readptr;
int sizeleft;
};
size_t read_callback(void *ptr, size_t size, size_t nmemb, void *userp)
{
struct WriteThis *pooh = (struct WriteThis *)userp;
if(size*nmemb < 1)
return 0;
if(pooh->sizeleft) {
*(char *)ptr = pooh->readptr[0]; /* copy one single byte */
pooh->readptr++; /* advance pointer */
pooh->sizeleft--; /* less data left */
return 1; /* we return 1 byte at a time! */
}
return -1; /* no more data left to deliver */
}
int main(void)
{
CURL *curl;
CURLcode res;
struct WriteThis pooh;
pooh.readptr = data;
pooh.sizeleft = strlen(data);
curl = curl_easy_init();
if(curl) {
/* First set the URL that is about to receive our POST. */
curl_easy_setopt(curl, CURLOPT_URL,
"http://receivingsite.com.pooh/index.cgi");
/* Now specify we want to POST data */
curl_easy_setopt(curl, CURLOPT_POST, TRUE);
/* Set the expected POST size */
curl_easy_setopt(curl, CURLOPT_POSTFIELDSIZE, pooh.sizeleft);
/* we want to use our own read function */
curl_easy_setopt(curl, CURLOPT_READFUNCTION, read_callback);
/* pointer to pass to our read function */
curl_easy_setopt(curl, CURLOPT_INFILE, &pooh);
/* get verbose debug output please */
curl_easy_setopt(curl, CURLOPT_VERBOSE, 1);
/* Perform the request, res will get the return code */
res = curl_easy_perform(curl);
/* always cleanup */
curl_easy_cleanup(curl);
}
return 0;
}