[tex-live] tlmgr w/ --machine-readable uses incorrect file descriptor

[Yudai NAKATA]

Dear all,

I noticed that tlmgr with --machine-readable option seems to use stderr
even when the exit status is 0.

$ tlmgr --version > human.stdout 2> human.stderr
$ tlmgr --version --machine-readable > machine.stdout 2> machine.stderr
$ echo $?
0
$ cat human.stdout
tlmgr revision 46034 (2017-12-11 02:54:21 +0100)
tlmgr using installation: /usr/local/texlive/2017
TeX Live (http://tug.org/texlive) version 2017
$ cat machine.stderr
revision 46034
installation /usr/local/texlive/2017
tlversion 2017
TLConfig 45617
TLUtils 46045

IMHO, I don’t think this is a good idea. Machine readable output is
often intended
to be used in conjunction with other programs, so it should use stdout
unless there
is some error.

Best regards,
Yudai Nakata