From a607f8a20c6c5ac869598753097e3da06165cbd9 Mon Sep 17 00:00:00 2001 From: Jay Satiro Date: Fri, 14 Nov 2014 03:59:46 -0500 Subject: examples: Don't call select() to sleep on windows Windows does not support using select() for sleeping without a dummy socket. Instead use Windows' Sleep() and sleep for 100ms which is the minimum suggested value in the curl_multi_fdset() doc. Prior to this change the multi examples would exit prematurely since select() would error instead of sleeping when called without an fd. Reported-by: Johan Lantz Bug: http://curl.haxx.se/mail/lib-2014-11/0221.html --- docs/examples/fopen.c | 31 ++++++++++++++++++++++++------- 1 file changed, 24 insertions(+), 7 deletions(-) (limited to 'docs/examples/fopen.c') diff --git a/docs/examples/fopen.c b/docs/examples/fopen.c index 6fe5c0f9f..c26c0de04 100644 --- a/docs/examples/fopen.c +++ b/docs/examples/fopen.c @@ -128,6 +128,7 @@ static int fill_buffer(URL_FILE *file, size_t want) fd_set fdexcep; struct timeval timeout; int rc; + CURLMcode mc; /* curl_multi_fdset() return code */ /* only attempt to fill buffer if transactions still running and buffer * doesnt exceed required size already @@ -158,15 +159,31 @@ static int fill_buffer(URL_FILE *file, size_t want) } /* get file descriptors from the transfers */ - curl_multi_fdset(multi_handle, &fdread, &fdwrite, &fdexcep, &maxfd); + mc = curl_multi_fdset(multi_handle, &fdread, &fdwrite, &fdexcep, &maxfd); - /* In a real-world program you OF COURSE check the return code of the - function calls. On success, the value of maxfd is guaranteed to be - greater or equal than -1. We call select(maxfd + 1, ...), specially - in case of (maxfd == -1), we call select(0, ...), which is basically - equal to sleep. */ + if(mc != CURLM_OK) + { + fprintf(stderr, "curl_multi_fdset() failed, code %d.\n", mc); + break; + } - rc = select(maxfd+1, &fdread, &fdwrite, &fdexcep, &timeout); + /* On success the value of maxfd is guaranteed to be >= -1. We call + select(maxfd + 1, ...); specially in case of (maxfd == -1) we call + select(0, ...), which is basically equal to sleeping the timeout. On + Windows we can't sleep via select without a dummy socket and instead + we Sleep() for 100ms which is the minimum suggested value in the + curl_multi_fdset() doc. */ + +#ifdef _WIN32 + if(maxfd == -1) { + Sleep(100); + rc = 0; + } + else +#endif + { + rc = select(maxfd+1, &fdread, &fdwrite, &fdexcep, &timeout); + } switch(rc) { case -1: -- cgit v1.2.3