GNU bug report logs - #32198
tail -f -F unexpected behavior

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Subject: tail -f -F unexpected behavior
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This is for tail v8.28 encountered on Ubuntu 18.04.

I was doing some experimentation with nano v2.9.3 and tail,
watching the output of tail after saving in nano and encountered some
strange behavior.

I had two terminals open side by side; one with nano and one with tail.
I opened a file called test.txt in nano and saved with ^w in the first
terminal.
I went to the second terminal and ran tail -f test.txt to watch the file.

I went back to the nano terminal and returned twice and saved.
The tail terminal reports this change properly.
With the file still open in nano, I write any number of characters and save.

The tail terminal reports this change But skips the first character. I also
tested this with -F.

This may not be an issue because it only happens when using the
write(ctrl-o, ctrl-s) in nano and not closing the file.

I have reproduced this on two machines.

--0000000000001c20b7057146d1fd
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<div dir=3D"ltr">This is for tail v8.28 encountered on Ubuntu 18.04.<div><b=
r></div><div>I was doing some experimentation with nano v2.9.3 and tail,</d=
iv><div>watching the output of tail after saving in nano and encountered so=
me strange behavior.</div><div><br></div><div>I had two terminals open side=
 by side; one with nano and one with tail.</div><div>I opened a file called=
 test.txt in nano and saved with ^w in the first terminal.</div><div>I went=
 to the second terminal and ran tail -f test.txt to watch the file.</div><d=
iv><br></div><div>I went back to the nano terminal and returned twice and s=
aved.</div><div>The tail terminal reports this change properly.</div><div>W=
ith the file still open in nano, I write any number of characters and save.=
</div><div><br></div><div>The tail terminal reports this change But skips t=
he first character. I also tested this with -F.</div><div><br></div><div>Th=
is may not be an issue because it only happens when using the write(ctrl-o,=
 ctrl-s) in nano and not closing the file.</div><div><br></div><div>I have =
reproduced this on two machines.</div><div><br></div><div><br></div></div>

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