How does apt/dpkg choose which real package is installed when a virtual package is specified as a dependency?












2














e.g. if package specifies 



Depends: www-browser


How does apt/dpkg decide which real package will be installed?






apt dpkg aptitude







share|improve this question





























    2














    e.g. if package specifies 



    Depends: www-browser


    How does apt/dpkg decide which real package will be installed?






    apt dpkg aptitude







    share|improve this question



























      2












      2








      2







      e.g. if package specifies 



      Depends: www-browser


      How does apt/dpkg decide which real package will be installed?






      apt dpkg aptitude







      share|improve this question















      e.g. if package specifies 



      Depends: www-browser


      How does apt/dpkg decide which real package will be installed?






      apt dpkg aptitude




      apt dpkg aptitude






      share|improve this question















      share|improve this question













      share|improve this question




      share|improve this question








      edited 41 mins ago









      peterh

      4,28592957




      4,28592957










      asked 3 hours ago









      the_velour_fog

      5,24533360




      5,24533360






















          1 Answer
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          active

          oldest

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          2














          According to this answer on Ask Ubuntu, apt will first try to install any non-virtual packages listed as options instead:




          Now, according to sources, apt tries first of satisfying the dependency before trying with virtual packages (i.e., if depends are firefox | www-browser, checks if any of the packages are installed, then try to install firefox if neither is).




          If not, it will simply iterate over the list of packages that provide the virtual one, and install the first one that it can:




          If the non-virtual package isn't available, it seems to just iterate over all packages which provides the virtual package, if no other dependencies are broken. Other comments evidence of this behavior are this which leads to GrpIterator::FindPreferredPkg function.







          share|improve this answer





















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            1 Answer
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            active

            oldest

            votes









            active

            oldest

            votes






            active

            oldest

            votes









            2














            According to this answer on Ask Ubuntu, apt will first try to install any non-virtual packages listed as options instead:




            Now, according to sources, apt tries first of satisfying the dependency before trying with virtual packages (i.e., if depends are firefox | www-browser, checks if any of the packages are installed, then try to install firefox if neither is).




            If not, it will simply iterate over the list of packages that provide the virtual one, and install the first one that it can:




            If the non-virtual package isn't available, it seems to just iterate over all packages which provides the virtual package, if no other dependencies are broken. Other comments evidence of this behavior are this which leads to GrpIterator::FindPreferredPkg function.







            share|improve this answer


























              2














              According to this answer on Ask Ubuntu, apt will first try to install any non-virtual packages listed as options instead:




              Now, according to sources, apt tries first of satisfying the dependency before trying with virtual packages (i.e., if depends are firefox | www-browser, checks if any of the packages are installed, then try to install firefox if neither is).




              If not, it will simply iterate over the list of packages that provide the virtual one, and install the first one that it can:




              If the non-virtual package isn't available, it seems to just iterate over all packages which provides the virtual package, if no other dependencies are broken. Other comments evidence of this behavior are this which leads to GrpIterator::FindPreferredPkg function.







              share|improve this answer
























                2












                2








                2






                According to this answer on Ask Ubuntu, apt will first try to install any non-virtual packages listed as options instead:




                Now, according to sources, apt tries first of satisfying the dependency before trying with virtual packages (i.e., if depends are firefox | www-browser, checks if any of the packages are installed, then try to install firefox if neither is).




                If not, it will simply iterate over the list of packages that provide the virtual one, and install the first one that it can:




                If the non-virtual package isn't available, it seems to just iterate over all packages which provides the virtual package, if no other dependencies are broken. Other comments evidence of this behavior are this which leads to GrpIterator::FindPreferredPkg function.







                share|improve this answer












                According to this answer on Ask Ubuntu, apt will first try to install any non-virtual packages listed as options instead:




                Now, according to sources, apt tries first of satisfying the dependency before trying with virtual packages (i.e., if depends are firefox | www-browser, checks if any of the packages are installed, then try to install firefox if neither is).




                If not, it will simply iterate over the list of packages that provide the virtual one, and install the first one that it can:




                If the non-virtual package isn't available, it seems to just iterate over all packages which provides the virtual package, if no other dependencies are broken. Other comments evidence of this behavior are this which leads to GrpIterator::FindPreferredPkg function.








                share|improve this answer












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                share|improve this answer










                answered 3 hours ago









                Nonny Moose

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