[FFmpeg-trac] #2740(undetermined:new): Concatenating m4a files FAILED with output file name 'con.m4a'

[FFmpeg]

#2740: Concatenating m4a files FAILED with output file name 'con.m4a'
-------------------------------------+-------------------------------------
             Reporter:  yumeyao      |                     Type:  defect
               Status:  new          |                 Priority:  minor
            Component:               |                  Version:
  undetermined                       |  unspecified
             Keywords:               |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------
 Summary of the bug:
 It seems the name 'con.m4a' is internally used or somewhat, I saw this
 message:
 {{{
 Input #0, concat, from 'mylist.txt':
   Duration: 00:00:00.00, start: 0.000000, bitrate: 163 kb/s
     Stream #0:0: Audio: aac (mp4a / 0x6134706D), 44100 Hz, stereo, fltp,
 162 kb/s
 File 'con.m4a' already exists. Overwrite ? [y/N]
 }}}

 Of course there's no such file there.

 If I choose Yes:
 {{{
 [ipod @ 0261d2c0] muxer does not support non seekable output
 Output #0, ipod, to 'con.m4a':
   Metadata:
     encoder         : Lavf55.10.100
     Stream #0:0: Audio: aac (mp4a / 0x6134706D), 44100 Hz, stereo, 162
 kb/s
 Stream mapping:
   Stream #0:0 -> #0:0 (copy)
 Could not write header for output file #0 (incorrect codec parameters ?):
 Error number -1 occurred
 }}}

 And yes, just by changing the output file name, the whole process goes to
 work.


 How to reproduce:
 {{{
 % ffmpeg -f concat -i mylist.txt -c copy con.m4a
 ffmpeg version N-54277-gff130d7 Copyright (c) 2000-2013 the FFmpeg
 developers
   built on Jun 30 2013 01:20:12 with gcc 4.7.3 (GCC)
 }}}

 (This is the version from http://ffmpeg.zeranoe.com/builds/, I was just
 lazy to build it myself because I just wanted to try out the concat
 function instructed in the wiki:
 [http://ffmpeg.org/trac/ffmpeg/wiki/How%20to%20concatenate%20(join,%20merge)%20media%20files]

 mylist.txt content:
 {{{
 1.m4a
 2.m4a
 }}}

-- 
Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/2740>
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