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FreeBSD user joining your ranks. I've been asked to look after an Ubuntu Server running 10.04 LTS.

I see from /usr/lib/update-notifier/update-motd-updates-available that there are a number of updates on the server however I do not see a way to tell which will be updated.

Would anyone be able to point me in the right direction so as I can see which packages will get updated when I run apt-get upgrade?

UPDATE:

Can't answer my own question at the moment so throwing this in here for the time being:

Along with the apt-get upgrade --dry-run suggested below, /usr/lib/update-notifier/apt-check -p will list all packages that have updates available.

muru
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Jan Geep
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4 Answers4

112

As of now (Ubuntu 16.04) you can use apt list with the --upgradable flag;

sudo apt update
apt list --upgradable

and you will get a list with all upgradable packages.

doru
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70

You could install aptitude if it isn't already installed. It's a great tool for managing packages in a headless setup.

enter image description here

Otherwise if you just want to see what's going to happen when you run something, use the --dry-run argument and it won't actually do anything, it'll just tell you what it would do:

From the apt-get man page

-s, --simulate, --just-print, --dry-run, --recon, --no-act
          No action; perform a simulation of events that would occur but do
          not actually change the system. Configuration Item:
          APT::Get::Simulate.
      Simulate prints out a series of lines each one representing a dpkg
      operation, Configure (Conf), Remove (Remv), Unpack (Inst). Square
      brackets indicate broken packages with and empty set of square
      brackets meaning breaks that are of no consequence (rare).

Add the option to the command this way

apt upgrade --dry-run
Oli
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    I disfigured your answer, hope you don't mind. – Bruno Pereira Jan 30 '12 at 10:44
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    Interestingly apt-get upgrade --dry-run doesn't require sudo, which makes it perfect for an automated display of required package updates. – dshepherd Mar 04 '15 at 15:33
  • even more interesting is, that on my Ubuntu 14.04 LTS "apt-get -s update" doesn't accept "-s"... nor "--dry-run", "--no-act"... why would that be? – mBardos Jun 08 '17 at 12:04
  • @mBardos Have you replaced the apt-get in your path with a "helper" script? Check which apt-get to make sure it's /usr/bin/apt-get – Oli Jun 09 '17 at 08:14
  • martonb@martonb-ubu:~/work/qt$ which apt-get /usr/bin/apt-get

    Does this work for you on Ubuntu 14.04 LTS?

    martonb@martonb-ubu:~/work/qt$ apt-get -s update
    E: Command line option 's' [from -s] is not known.
    
    – mBardos Jun 09 '17 at 10:57
  • You don't need sudo when you use --dry-run. – Ruslan Oct 17 '18 at 09:51
12

Below command will show you the list of installed packages which has an update available in the repositories.

dpkg --get-selections | xargs apt-cache policy {} | grep -1 Installed | sed -r 's/(:|Installed: |Candidate: )//' | uniq -u | tac | sed '/--/I,+1 d' | tac | sed '$d' | sed -n 1~2p
Avinash Raj
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    That's a nice bit of command line magic! – Teemu Leisti Dec 18 '15 at 09:55
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    Nice, but @sierrasdetandil’s and @doru’ answers do exactly the same in a beautifully concise way... – Giuseppe Oct 05 '16 at 08:13
  • Yes, but aptitude is an additional install and apt doesn't like to be scripted. – Mausy5043 Feb 13 '22 at 08:32
  • @Avinash Raj Did you mean to include --ignore-case or -i instead of 1 at the command pipe segment grep -1 Installed? Did you mean -A 1 by any chance, because they have the same output! I wonder about this behavior and whether there was a placeholding variable flag for grep that can be substituted directly with a number! – xquilt Aug 25 '22 at 18:20
12

Another alternative would be to use aptitude with a search term:

aptitude search '~U'

(Note the uppercase 'U')

That means: "search for all packages that are installed and can be upgraded". Reference: aptitude user's manual

By default, aptitude search shows for each package its name, description and a few flags, but you could also adapt the output to your needs. For example, to list only the package names, the command would be:

aptitude search -F '%p' --disable-columns '~U'

(--disable-columns avoids padding whitespace at the end of the lines)

sierrasdetandil
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