How does debian/ubuntu knows a package has a updated version





.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty{ height:90px;width:728px;box-sizing:border-box;
}







1















If my understanding is good, with apt update, Debian download a release file and with this file, it can tell if a package needs to be upgraded and with which dependencies. How does it do this? Th release file seems to be just a list of hashes so I don't quite understand.



Sorry, I don't have a very good English.










share|improve this question







New contributor




thomas is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.



























    1















    If my understanding is good, with apt update, Debian download a release file and with this file, it can tell if a package needs to be upgraded and with which dependencies. How does it do this? Th release file seems to be just a list of hashes so I don't quite understand.



    Sorry, I don't have a very good English.










    share|improve this question







    New contributor




    thomas is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
    Check out our Code of Conduct.























      1












      1








      1








      If my understanding is good, with apt update, Debian download a release file and with this file, it can tell if a package needs to be upgraded and with which dependencies. How does it do this? Th release file seems to be just a list of hashes so I don't quite understand.



      Sorry, I don't have a very good English.










      share|improve this question







      New contributor




      thomas is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.












      If my understanding is good, with apt update, Debian download a release file and with this file, it can tell if a package needs to be upgraded and with which dependencies. How does it do this? Th release file seems to be just a list of hashes so I don't quite understand.



      Sorry, I don't have a very good English.







      ubuntu debian apt






      share|improve this question







      New contributor




      thomas is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.











      share|improve this question







      New contributor




      thomas is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.









      share|improve this question




      share|improve this question






      New contributor




      thomas is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.









      asked 4 hours ago









      thomasthomas

      82




      82




      New contributor




      thomas is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.





      New contributor





      thomas is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.






      thomas is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.






















          2 Answers
          2






          active

          oldest

          votes


















          2














          Whilst apt update can download one or more Release files, the primary files it is downloading are Packages file(s). Those files contain the full list of available packages, their versions, and other metadata (like dependencies). Once apt has a list of available packages and their versions, it is a straightforward matter of comparison to determine which packages have versions newer than those currently installed.






          share|improve this answer
























          • Thanks a lot for this.

            – thomas
            3 hours ago



















          1














          Package lists are the Packages and Sources files. These contain the debian/control file content for every package in the repository. From these metadata APT can determine a dependency solution.



          Releases is a description of the entire archive and signature data.



          Debian reference manual, Chapter 2. Debian package management






          share|improve this answer
























            Your Answer








            StackExchange.ready(function() {
            var channelOptions = {
            tags: "".split(" "),
            id: "2"
            };
            initTagRenderer("".split(" "), "".split(" "), channelOptions);

            StackExchange.using("externalEditor", function() {
            // Have to fire editor after snippets, if snippets enabled
            if (StackExchange.settings.snippets.snippetsEnabled) {
            StackExchange.using("snippets", function() {
            createEditor();
            });
            }
            else {
            createEditor();
            }
            });

            function createEditor() {
            StackExchange.prepareEditor({
            heartbeatType: 'answer',
            autoActivateHeartbeat: false,
            convertImagesToLinks: true,
            noModals: true,
            showLowRepImageUploadWarning: true,
            reputationToPostImages: 10,
            bindNavPrevention: true,
            postfix: "",
            imageUploader: {
            brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
            contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
            allowUrls: true
            },
            onDemand: true,
            discardSelector: ".discard-answer"
            ,immediatelyShowMarkdownHelp:true
            });


            }
            });






            thomas is a new contributor. Be nice, and check out our Code of Conduct.










            draft saved

            draft discarded


















            StackExchange.ready(
            function () {
            StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fserverfault.com%2fquestions%2f963386%2fhow-does-debian-ubuntu-knows-a-package-has-a-updated-version%23new-answer', 'question_page');
            }
            );

            Post as a guest















            Required, but never shown

























            2 Answers
            2






            active

            oldest

            votes








            2 Answers
            2






            active

            oldest

            votes









            active

            oldest

            votes






            active

            oldest

            votes









            2














            Whilst apt update can download one or more Release files, the primary files it is downloading are Packages file(s). Those files contain the full list of available packages, their versions, and other metadata (like dependencies). Once apt has a list of available packages and their versions, it is a straightforward matter of comparison to determine which packages have versions newer than those currently installed.






            share|improve this answer
























            • Thanks a lot for this.

              – thomas
              3 hours ago
















            2














            Whilst apt update can download one or more Release files, the primary files it is downloading are Packages file(s). Those files contain the full list of available packages, their versions, and other metadata (like dependencies). Once apt has a list of available packages and their versions, it is a straightforward matter of comparison to determine which packages have versions newer than those currently installed.






            share|improve this answer
























            • Thanks a lot for this.

              – thomas
              3 hours ago














            2












            2








            2







            Whilst apt update can download one or more Release files, the primary files it is downloading are Packages file(s). Those files contain the full list of available packages, their versions, and other metadata (like dependencies). Once apt has a list of available packages and their versions, it is a straightforward matter of comparison to determine which packages have versions newer than those currently installed.






            share|improve this answer













            Whilst apt update can download one or more Release files, the primary files it is downloading are Packages file(s). Those files contain the full list of available packages, their versions, and other metadata (like dependencies). Once apt has a list of available packages and their versions, it is a straightforward matter of comparison to determine which packages have versions newer than those currently installed.







            share|improve this answer












            share|improve this answer



            share|improve this answer










            answered 3 hours ago









            womblewomble

            85.8k18145204




            85.8k18145204













            • Thanks a lot for this.

              – thomas
              3 hours ago



















            • Thanks a lot for this.

              – thomas
              3 hours ago

















            Thanks a lot for this.

            – thomas
            3 hours ago





            Thanks a lot for this.

            – thomas
            3 hours ago













            1














            Package lists are the Packages and Sources files. These contain the debian/control file content for every package in the repository. From these metadata APT can determine a dependency solution.



            Releases is a description of the entire archive and signature data.



            Debian reference manual, Chapter 2. Debian package management






            share|improve this answer




























              1














              Package lists are the Packages and Sources files. These contain the debian/control file content for every package in the repository. From these metadata APT can determine a dependency solution.



              Releases is a description of the entire archive and signature data.



              Debian reference manual, Chapter 2. Debian package management






              share|improve this answer


























                1












                1








                1







                Package lists are the Packages and Sources files. These contain the debian/control file content for every package in the repository. From these metadata APT can determine a dependency solution.



                Releases is a description of the entire archive and signature data.



                Debian reference manual, Chapter 2. Debian package management






                share|improve this answer













                Package lists are the Packages and Sources files. These contain the debian/control file content for every package in the repository. From these metadata APT can determine a dependency solution.



                Releases is a description of the entire archive and signature data.



                Debian reference manual, Chapter 2. Debian package management







                share|improve this answer












                share|improve this answer



                share|improve this answer










                answered 3 hours ago









                John MahowaldJohn Mahowald

                8,9111713




                8,9111713






















                    thomas is a new contributor. Be nice, and check out our Code of Conduct.










                    draft saved

                    draft discarded


















                    thomas is a new contributor. Be nice, and check out our Code of Conduct.













                    thomas is a new contributor. Be nice, and check out our Code of Conduct.












                    thomas is a new contributor. Be nice, and check out our Code of Conduct.
















                    Thanks for contributing an answer to Server Fault!


                    • Please be sure to answer the question. Provide details and share your research!

                    But avoid



                    • Asking for help, clarification, or responding to other answers.

                    • Making statements based on opinion; back them up with references or personal experience.


                    To learn more, see our tips on writing great answers.




                    draft saved


                    draft discarded














                    StackExchange.ready(
                    function () {
                    StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fserverfault.com%2fquestions%2f963386%2fhow-does-debian-ubuntu-knows-a-package-has-a-updated-version%23new-answer', 'question_page');
                    }
                    );

                    Post as a guest















                    Required, but never shown





















































                    Required, but never shown














                    Required, but never shown












                    Required, but never shown







                    Required, but never shown

































                    Required, but never shown














                    Required, but never shown












                    Required, but never shown







                    Required, but never shown







                    Popular posts from this blog

                    GameSpot

                    日野市

                    Tu-95轟炸機