On Mon, Feb 03, 2025 at 23:33:50 -0500, gene heskett wrote:
> gene@coyote:/$ sudo -i
> root@coyote:~# comm -23 <(dpkg-query -W -f '${Package} ${Version}\n' | sort
> -u)
> <(apt-cache dumpavail | awk '/^Package:/ {package = $NF} /^Version:/
> {version = $NF} /^$/ {print package, version}' | sort -u)
> comm: missing operand after ‘/dev/fd/63’
> Try 'comm --help' for more information.
> -bash: /dev/fd/63: Permission denied
Is there a newline in the middle of this command that shouldn't be
there?
The errors that you're seeing here are consistent with the comm -23
command only having ONE of the <() process substitutions as an argument,
and then the second <() proc sub being on a line by itself.
hobbit:~$ sudo -i
[sudo] password for greg:
root@hobbit:~# <(echo hi)
-bash: /dev/fd/63: Permission denied
I'm guessing you pasted the command out of a mail program or web browser,
in which the code had an extra newline added.
There should be a space (not a newline) between "-u)" and "<(apt-cache".
