[Bug-wget] wget in a 'dynamic' pipe

[Paul Wagner]

Dear wgetters,

apologies if this has been asked before.

I'm using wget to download DASH media files, i.e. a number of URLs in 
the form domain.com/path/segment_1.mp4, domain.com/path/segment_2.mp4, 
..., which represent chunks of audio or video, and which are to be 
combined to form the whole programme.  I used to call individuall 
instances of wget for each chunk and combine them, which was dead slow.  
Now I tried

  { i=1; while [[ $i != 100 ]]; do echo 
"http://domain.com/path/segment_$((i++)).mp4"; done } | wget -O foo.mp4 
-i -

which works like a charm *as long as the 'generator process' is finite*, 
i.e. the loop is actually programmed as in the example.  The problem is 
that it would be much easier if I could let the loop run forever, let 
wget get whatever is there and then fail after the counter extends to a 
segment number not available anymore, which would in turn fail the whole 
pipe.  Turns out that

  { i=1; while true; do echo 
"http://domain.com/path/segment_$((i++)).mp4"; done } | wget -O foo.mp4 
-i -

hangs in the sense that the first process loops forever while wget 
doesn't even bother to start retrieving.  Am I right assuming that wget 
waits until the file specified by -i is actually fully written?  Is 
there any way to change this behavour?

Any help appreciated.  (I'm using wget 1.19.1 under cygwin.)

Kind regards,

Paul