title: Adding 'timeout' flag to ffprobe/ffmpeg causes it to fail immediately
body: <p>If I run <code>ffprobe -timeout 20 -v trace -print_format json -show_format -show_streams 'http://www.sample-videos.com/video/mp4/720/big_buck_bunny_720p_2mb.mp4'</code>, the command fails immediately with a <code>Connection timed out</code> error even though I set the timeout to 20 seconds. It doesn't wait anywhere near 20 seconds, just exits right away with an exit code of 1. Here's the trace output.</p>
  
  <pre><code>ffprobe version 3.2.2 Copyright (c) 2007-2016 the FFmpeg developers
    built with gcc 6.2.1 (GCC) 20160830
    configuration: --prefix=/usr --disable-debug --disable-static --disable-stripping --enable-avisynth --enable-avresample --enable-fontconfig --enable-gmp --enable-gnutls --enable-gpl --enable-ladspa --enable-libass --enable-libbluray --enable-libfreetype --enable-libfribidi --enable-libgsm --enable-libiec61883 --enable-libmodplug --enable-libmp3lame --enable-libopencore_amrnb --enable-libopencore_amrwb --enable-libopenjpeg --enable-libopus --enable-libpulse --enable-libschroedinger --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libv4l2 --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxvid --enable-netcdf --enable-shared --enable-version3 --enable-x11grab
    libavutil      55. 34.100 / 55. 34.100
    libavcodec     57. 64.101 / 57. 64.101
    libavformat    57. 56.100 / 57. 56.100
    libavdevice    57.  1.100 / 57.  1.100
    libavfilter     6. 65.100 /  6. 65.100
    libavresample   3.  1.  0 /  3.  1.  0
    libswscale      4.  2.100 /  4.  2.100
    libswresample   2.  3.100 /  2.  3.100
    libpostproc    54.  1.100 / 54.  1.100
  {
  [http @ 0x5598e7df1e20] Setting default whitelist 'http,https,tls,rtp,tcp,udp,crypto,httpproxy'
  [http @ 0x5598e7df1e20] request: GET /video/mp4/720/big_buck_bunny_720p_2mb.mp4 HTTP/1.1
  User-Agent: Lavf/57.56.100
  Accept: */*
  Range: bytes=0-
  Connection: close
  Host: www.sample-videos.com
  Icy-MetaData: 1
  
  
  http://www.sample-videos.com/video/mp4/720/big_buck_bunny_720p_2mb.mp4: Connection timed out
  
  }
  </code></pre>
  
  <p>If I remove the <code>-timeout 20</code> flag the command works fine. How can I get <code>ffprobe</code> to work with timeouts?</p>