[solved - I hope] How do I fix messed up apt-get?

[doctordruidphd]

I tried to install a package, and it pulled an error message and refused to install:

greenman@Wolfenstein:~/Downloads$ sudo dpkg -i iscan_2.19.0-4_amd64.deb
[sudo] password for greenman:
(Reading database ... 358837 files and directories currently installed.)
Unpacking iscan (from iscan_2.19.0-4_amd64.deb) ...
/var/lib/dpkg/tmp.ci/preinst: 29: Bad substitution
dpkg: error processing iscan_2.19.0-4_amd64.deb (--install):
 subprocess pre-installation script returned error exit status 2
Processing triggers for menu ...
Errors were encountered while processing:
 iscan_2.19.0-4_amd64.deb

Need this to run my scanner; figures it wouldn't work.
So I attempted to remove it:

greenman@Wolfenstein:~/Downloads$ sudo dpkg --remove iscan-interpreter
dpkg - warning: ignoring request to remove iscan-interpreter which isn't installed.

And just to make sure, did an apt-get clean.
Then, when I try to update:

greenman@Wolfenstein:~$ sudo apt-get update
[archive lists snipped]
Fetched 6259kB in 35s (174kB/s)
Reading package lists... Done
W: Ignoring Provides line with DepCompareOp for package iscan-interpreter
W: You may want to run apt-get update to correct these problems

I can't get rid of the miserable thing. Tried purging, cleaning, and it still doesn't go away.
Any idea what has happened, and how to clean it out?

Addendum:

greenman@Wolfenstein:~$ dpkg-query --show iscan*
iscan
iscan-interpreter
iscan-plugin-cx4400
iscan-plugin-gt-7200
iscan-plugin-gt-7300
iscan-plugin-gt-9400
iscan-plugin-gt-f500
iscan-plugin-gt-f520
iscan-plugin-gt-f600
iscan-plugin-gt-f670
iscan-plugin-gt-f700
iscan-plugin-gt-s600
iscan-plugin-gt-x750

It's still there, and trying to purge or remove doesn't flush it.

[mfabry]

Re: How do I fix messed up apt-get?

Have you tried by any chance "apt-get install -f"?

[flarson]

Re: How do I fix messed up apt-get?

The way you ran dpkg-query it is not telling you if those packages are installed or if they have been installed and then removed but not purged. You probably do not have a problem at all anymore. If you do sudo aptitude -f install
will probably fix it.

If you run dpkg -l | grep iscan
it will show you the state of the package. You will probably see many rc for removed but config files still on the system.
If you want to purge them try
sudo aptitude purge packagename
or
sudo dpkg --purge packagename

[doctordruidphd]

Re: How do I fix messed up apt-get?

Thanks for the suggestions. I tried all of those. Example:

greenman@Wolfenstein:~$ sudo aptitude purge iscan_2.19.0-4_amd64.deb
Reading package lists... Done                    
Building dependency tree
Reading state information... Done
Reading extended state information
Initializing package states... Done
Couldn't find any package whose name or description matched "iscan_2.19.0-4_amd64.deb"
Couldn't find any package whose name or description matched "iscan_2.19.0-4_amd64.deb"

And:

greenman@Wolfenstein:~$ sudo dpkg --purge iscan*
[sudo] password for greenman:          
dpkg - warning: ignoring request to remove iscan* which isn't installed.

But it's still there:

greenman@Wolfenstein:~$ sudo apt-get update                 
Get:1 [url]http://us.archive.ubuntu.com[/url] jaunty Release.gpg [189B]          
Ign [url]http://us.archive.ubuntu.com[/url] jaunty/main Translation-en_US         
Hit [url]http://download.virtualbox.org[/url] intrepid/non-free Packages          
[etc. etc.]
Hit [url]http://us.archive.ubuntu.com[/url] jaunty-proposed/main Packages
Hit [url]http://us.archive.ubuntu.com[/url] jaunty-proposed/multiverse Packages
Hit [url]http://us.archive.ubuntu.com[/url] jaunty-proposed/universe Packages
Fetched 6260kB in 35s (175kB/s)
Reading package lists... Done
W: Ignoring Provides line with DepCompareOp for package iscan-interpreter
W: You may want to run apt-get update to correct these problems

Well, it's buried itself in there somewhere.

[dibl]

Re: How do I fix messed up apt-get?

You can try

sudo apt-get autoremove

that is pretty good at stripping out stuff that isn't actually installed or a dependency on something that is installed.

[doctordruidphd]

Re: How do I fix messed up apt-get?

Just tried that. No luck. Error message is still there.
Any ideas where the "W:" part is coming from?
If dpkg-configure can find it, it's still in a database somewhere. This is a package I downloaded, and is not in any repository. I seem to recall during a backup seeing a whole list of stuff dpkg keeps of what it has seen, but I sure can't find it now that I need to.

[dibl]

Re: How do I fix messed up apt-get?

This:

W: You may want to run apt-get update to correct these problems

is a somewhat generic message that is put up when any of a number of conditions is encountered. It's quite unhelpful.

I forget -- if haven't already run

sudo dpkg --configure -a

you need to do that. If no errors are generated, then that would indicate that your package database itself is fine.

Then I would check your sources and see if there is a non-standard repository (not a ubuntu or medibuntu repo). Try commenting it out of the sources.list file, and then run the apt-get update command again. This is on the chance that the error may be coming from a repo rather than from your system.

[doctordruidphd]

Re: How do I fix messed up apt-get?

OK, tried that. No errors from dpkg --configure -a.
Removed all non-ubuntu repositories. Error still there on update.

Here's a bit of a dilemma:

greenman@Wolfenstein:~$ dpkg-query -l iscan*      
Desired=Unknown/Install/Remove/Purge/Hold       
| Status=Not/Inst/Cfg-files/Unpacked/Failed-cfg/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Hold/Reinst-required/X=both-problems (Status,Err: uppercase=bad)
||/ Name     Version    Description                 
+++-==============-==============-============================================ 
in iscan     <none>    (no description available)
un iscan-interpre <none>    (no description available)
un iscan-plugin-c <none>    (no description available)
un iscan-plugin-g <none>    (no description available)
un iscan-plugin-g <none>    (no description available)
un iscan-plugin-g <none>    (no description available)
un iscan-plugin-g <none>    (no description available)
un iscan-plugin-g <none>    (no description available)
un iscan-plugin-g <none>    (no description available)
un iscan-plugin-g <none>    (no description available)
un iscan-plugin-g <none>    (no description available)
un iscan-plugin-g <none>    (no description available)
un iscan-plugin-g <none>    (no description available)
greenman@Wolfenstein:~$ sudo dpkg --purge iscan
dpkg - warning: ignoring request to remove iscan which isn't installed.

Seems dpkg-query thinks it it installed, but purge can't find it to remove, if I'm reading this right.
Maybe this is much ado about nothing, but if the package database is corrupt in some way, it may come back to haunt later.
FYI: Synaptic is pulling the same error on startup:
W: Ignoring Provides line with DepCompareOp for package iscan-interpreter

I've just got a bad feeling about this...

[dibl]

Re: How do I fix messed up apt-get?

That's an odd one. I've always understood that if the dpkg --configure -a command results in a happy dpkg system, then you can breathe easy.

I think maybe there is a bit of iscan that was installed, but not all of it. I don't know if you can use a "-f" switch on "--purge" or not. You might be better off waiting to see whether future problems arise -- sometimes chasing non-problems can actually induce new problems.

[doctordruidphd]

Re: How do I fix messed up apt-get?

I think I found it.

It's buried in the file:
/var/lib/dpkg/status

It might be courting disaster to mess with it, but I removed the entries for the two packages that I tried to install. Seems to have fixed the problem; dpkg-query now knows nothing about them, and the error messages from update are gone.

[dibl]

Re: How do I fix messed up apt-get?

It's buried in the file:
/var/lib/dpkg/status

Aha! Great catch, Dr. D!