[root@a upfc]# ./ffmpeg-linux64-v3.3.1 -i a.mp3

ffmpeg version N-86111-ga441aa90e8-static http://johnvansickle.com/ffmpeg/  Copyright (c) 2000-2017 the FFmpeg developers

  built with gcc 5.4.1 (Debian 5.4.1-8) 20170304

  configuration: --enable-gpl --enable-version3 --enable-static --disable-debug --disable-ffplay --disable-indev=sndio --disable-outdev=sndio --cc=gcc-5 --enable-fontconfig --enable-frei0r --enable-gnutls --enable-gray --enable-libass --enable-libfreetype --enable-libfribidi --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libvidstab --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxvid --enable-libzimg

  libavutil      55. 63.100 / 55. 63.100

  libavcodec     57. 96.101 / 57. 96.101

  libavformat    57. 72.101 / 57. 72.101

  libavdevice    57.  7.100 / 57.  7.100

  libavfilter     6. 89.101 /  6. 89.101

  libswscale      4.  7.101 /  4.  7.101

  libswresample   2.  8.100 /  2.  8.100

  libpostproc    54.  6.100 / 54.  6.100

[mp3 @ 0x4f60420] Estimating duration from bitrate, this may be inaccurate

Input #0, mp3, from 'a.mp3':

  Duration: 00:02:00.85, start: 0.000000, bitrate: 16 kb/s

    Stream #0:0: Audio: mp3, 16000 Hz, mono, s16p, 16 kb/s

At least one output file must be specified

[root@a upfc]# ./ffmpeg-linux64-v3.3.1 -i a.mp3