appimaged floods stderr with underscores

[mithrandi]

When I start appimaged, it outputs a seemingly unlimited number of lines containing only _________________________; these end up in the journal when autostarted normally which is rather frustrating, although most of them do get collapsed fortunately.

My system info:

mithrandi@lorien ~> appimaged --version
appimaged, continuous build (commit 485198d), build 1697 built on 2018-04-26 18:10:12 UTC
mithrandi@lorien ~> lsb_release -a
No LSB modules are available.
Distributor ID: Debian
Description:    Debian GNU/Linux unstable (sid)
Release:        unstable
Codename:       sid
mithrandi@lorien ~> uname -a
Linux lorien 4.15.0-3-amd64 #1 SMP Debian 4.15.17-1 (2018-04-19) x86_64 GNU/Linux

Let me know if there's any extra debugging I can do or information I should provide.

[probonopd]

That is interesting. The _________________________ is intended as a separator between each file that has been processed by appimaged. I implemented this and other debug output so that one can see what is going on when running it from the command line.

I have to admit that I never thought of the journal. Are you saying that appimaged should better not output debug information to stdout and stderr during normal operation?

[mithrandi]

Ah, I have tens of thousands of files in my Downloads directory, so that probably explains the volume of output. I think it would probably be better not to output "debug level" messages by default, or at least when not attached to a terminal. On non-systemd systems I think these messages will probably end up filling ~/.xsession-errors which is also not ideal.

[probonopd]

Should probably use https://linux.die.net/man/3/isatty and not output anything except errors if isatty(STDOUT_FILENO) == 0

[TheAssassin]

You could as well just use an environment variable. That way, systemd users could switch it on in the systemd settings as well.

[probonopd]

Like, only output debug messages, if the environment variable $DEBUG is not empty?

[TheAssassin]

Something like that, yes. That's a lot more explicit than some TTY checks.

[TheAssassin]

Migrated to AppImageCommunity/appimaged#18.