From cb13fad733e38cb8fbc1919e70d11d3c8b88ec52 Mon Sep 17 00:00:00 2001 From: Jay Satiro Date: Mon, 17 Nov 2014 02:26:03 -0500 Subject: examples: Wait recommended 100ms when no file descriptors are ready Prior to this change when no file descriptors were ready on platforms other than Windows the multi examples would sleep whatever was in timeout, which may or may not have been less than the minimum recommended value [1] of 100ms. [1]: http://curl.haxx.se/libcurl/c/curl_multi_fdset.html --- docs/examples/fopen.c | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) (limited to 'docs/examples/fopen.c') diff --git a/docs/examples/fopen.c b/docs/examples/fopen.c index c26c0de04..3d2a81773 100644 --- a/docs/examples/fopen.c +++ b/docs/examples/fopen.c @@ -168,20 +168,24 @@ static int fill_buffer(URL_FILE *file, size_t want) } /* 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 + 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. */ -#ifdef _WIN32 if(maxfd == -1) { +#ifdef _WIN32 Sleep(100); rc = 0; - } - else +#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); } -- cgit v1.2.3