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/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at https://curl.haxx.se/docs/copyright.html.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the COPYING file.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
***************************************************************************/
/* <DESC>
* POP3 example using the multi interface
* </DESC>
*/
#include <stdio.h>
#include <string.h>
#include <curl/curl.h>
/* This is a simple example showing how to retrieve mail using libcurl's POP3
* capabilities. It builds on the pop3-retr.c example to demonstrate how to use
* libcurl's multi interface.
*
* Note that this example requires libcurl 7.20.0 or above.
*/
#define MULTI_PERFORM_HANG_TIMEOUT 60 * 1000
static struct timeval tvnow(void)
{
struct timeval now;
/* time() returns the value of time in seconds since the epoch */
now.tv_sec = (long)time(NULL);
now.tv_usec = 0;
return now;
}
static long tvdiff(struct timeval newer, struct timeval older)
{
return (newer.tv_sec - older.tv_sec) * 1000 +
(newer.tv_usec - older.tv_usec) / 1000;
}
int main(void)
{
CURL *curl;
CURLM *mcurl;
int still_running = 1;
struct timeval mp_start;
curl_global_init(CURL_GLOBAL_DEFAULT);
curl = curl_easy_init();
if(!curl)
return 1;
mcurl = curl_multi_init();
if(!mcurl)
return 2;
/* Set username and password */
curl_easy_setopt(curl, CURLOPT_USERNAME, "user");
curl_easy_setopt(curl, CURLOPT_PASSWORD, "secret");
/* This will retrieve message 1 from the user's mailbox */
curl_easy_setopt(curl, CURLOPT_URL, "pop3://pop.example.com/1");
/* Tell the multi stack about our easy handle */
curl_multi_add_handle(mcurl, curl);
/* Record the start time which we can use later */
mp_start = tvnow();
/* We start some action by calling perform right away */
curl_multi_perform(mcurl, &still_running);
while(still_running) {
struct timeval timeout;
fd_set fdread;
fd_set fdwrite;
fd_set fdexcep;
int maxfd = -1;
int rc;
CURLMcode mc; /* curl_multi_fdset() return code */
long curl_timeo = -1;
/* Initialise the file descriptors */
FD_ZERO(&fdread);
FD_ZERO(&fdwrite);
FD_ZERO(&fdexcep);
/* Set a suitable timeout to play around with */
timeout.tv_sec = 1;
timeout.tv_usec = 0;
curl_multi_timeout(mcurl, &curl_timeo);
if(curl_timeo >= 0) {
timeout.tv_sec = curl_timeo / 1000;
if(timeout.tv_sec > 1)
timeout.tv_sec = 1;
else
timeout.tv_usec = (curl_timeo % 1000) * 1000;
}
/* get file descriptors from the transfers */
mc = curl_multi_fdset(mcurl, &fdread, &fdwrite, &fdexcep, &maxfd);
if(mc != CURLM_OK) {
fprintf(stderr, "curl_multi_fdset() failed, code %d.\n", mc);
break;
}
/* On success the value of maxfd is guaranteed to be >= -1. We call
select(maxfd + 1, ...); specially in case of (maxfd == -1) there are
no fds ready yet so we call select(0, ...) --or Sleep() on Windows--
to sleep 100ms, which is the minimum suggested value in the
curl_multi_fdset() doc. */
if(maxfd == -1) {
#ifdef _WIN32
Sleep(100);
rc = 0;
#else
/* Portable sleep for platforms other than Windows. */
struct timeval wait = { 0, 100 * 1000 }; /* 100ms */
rc = select(0, NULL, NULL, NULL, &wait);
#endif
}
else {
/* Note that on some platforms 'timeout' may be modified by select().
If you need access to the original value save a copy beforehand. */
rc = select(maxfd + 1, &fdread, &fdwrite, &fdexcep, &timeout);
}
if(tvdiff(tvnow(), mp_start) > MULTI_PERFORM_HANG_TIMEOUT) {
fprintf(stderr,
"ABORTING: Since it seems that we would have run forever.\n");
break;
}
switch(rc) {
case -1: /* select error */
break;
case 0: /* timeout */
default: /* action */
curl_multi_perform(mcurl, &still_running);
break;
}
}
/* Always cleanup */
curl_multi_remove_handle(mcurl, curl);
curl_multi_cleanup(mcurl);
curl_easy_cleanup(curl);
curl_global_cleanup();
return 0;
}
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