Problem solved (sort of) by commenting out lines in /etc/profile:
## include /etc/bash.bashrc if it exists
#if [ -f /etc/bash.bashrc ]; then
# . /etc/bash.bashrc
#fi
I had had this inclusion in /etc/profile for at least 15 years, and
this seemed to be the 1st time it caused a problem. I read "man dash"
and noticed Dash also uses /etc/profile, so probably Bash specific
configuration there is not a good idea anymore.
Update of Debian to Buster earlier asked about changing from sh to
dash, so I let it do it.
Error logs seem to be:
-sh: 11: /etc/bash.bashrc: shopt: not found
-sh: 35: /etc/bash.bashrc: shopt: not found
-sh: 26: /usr/share/bash-completion/bash_completion: Syntax error: "("
unexpected
This appears to come from the following command in the postinst script:
su -l sympa -s /bin/sh -c "/usr/lib/sympa/bin/sympa.pl
--upgrade_config_location"
Which shell is used for the Sympa user (getent passwd sympa) ?
Which shell is /bin/sh on your system?
# getent passwd sympa
sympa:x:148:159:Sympa mailing list manager,,,:/var/lib/sympa:/bin/false
# ls -al /bin/sh
lrwxrwxrwx 1 root root 4 Feb 10 2020 /bin/sh -> dash
It might be a similar problem
tohttps://bugs.debian.org/cgi-bin/bugreport.cgi?bug=737621.
Yes, directly related to bash / dash / sh shells. Older systems have
had different defaults during installation, which seems to backfire
sometimes.
