Why would /etc/passwd be used every time someone executes `ls -l` command?












1















Read from APUE, just feel curious:




The password file is used every time a user logs in to a
UNIX system and every time someone executes an ls -l command.







ls passwd







share|improve this question





























    1















    Read from APUE, just feel curious:




    The password file is used every time a user logs in to a
    UNIX system and every time someone executes an ls -l command.







    ls passwd







    share|improve this question



























      1












      1








      1








      Read from APUE, just feel curious:




      The password file is used every time a user logs in to a
      UNIX system and every time someone executes an ls -l command.







      ls passwd







      share|improve this question
















      Read from APUE, just feel curious:




      The password file is used every time a user logs in to a
      UNIX system and every time someone executes an ls -l command.







      ls passwd




      ls passwd






      share|improve this question















      share|improve this question













      share|improve this question




      share|improve this question








      edited 4 mins ago









      Olorin

      3,8681721




      3,8681721










      asked 1 hour ago









      RickRick

      1165




      1165






















          1 Answer
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          The file-system directly associates the numerical UID (User ID) and GID (Group ID) values with the file, not the user name and group name (which are strings). So the ls -l command (and any other command that displays the user and group owner of a file) need to get the user and group names from somewhere. The /etc/passwd file is one such source (probably the original and most common source). The manual bears this out - from PASSWD (5) (i.e. the man page for the /etc/passwd file):




          many utilities, like ls(1) use it to map user IDs to usernames







          share|improve this answer

























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            The file-system directly associates the numerical UID (User ID) and GID (Group ID) values with the file, not the user name and group name (which are strings). So the ls -l command (and any other command that displays the user and group owner of a file) need to get the user and group names from somewhere. The /etc/passwd file is one such source (probably the original and most common source). The manual bears this out - from PASSWD (5) (i.e. the man page for the /etc/passwd file):




            many utilities, like ls(1) use it to map user IDs to usernames







            share|improve this answer






























              1














              The file-system directly associates the numerical UID (User ID) and GID (Group ID) values with the file, not the user name and group name (which are strings). So the ls -l command (and any other command that displays the user and group owner of a file) need to get the user and group names from somewhere. The /etc/passwd file is one such source (probably the original and most common source). The manual bears this out - from PASSWD (5) (i.e. the man page for the /etc/passwd file):




              many utilities, like ls(1) use it to map user IDs to usernames







              share|improve this answer




























                1












                1








                1







                The file-system directly associates the numerical UID (User ID) and GID (Group ID) values with the file, not the user name and group name (which are strings). So the ls -l command (and any other command that displays the user and group owner of a file) need to get the user and group names from somewhere. The /etc/passwd file is one such source (probably the original and most common source). The manual bears this out - from PASSWD (5) (i.e. the man page for the /etc/passwd file):




                many utilities, like ls(1) use it to map user IDs to usernames







                share|improve this answer















                The file-system directly associates the numerical UID (User ID) and GID (Group ID) values with the file, not the user name and group name (which are strings). So the ls -l command (and any other command that displays the user and group owner of a file) need to get the user and group names from somewhere. The /etc/passwd file is one such source (probably the original and most common source). The manual bears this out - from PASSWD (5) (i.e. the man page for the /etc/passwd file):




                many utilities, like ls(1) use it to map user IDs to usernames








                share|improve this answer














                share|improve this answer



                share|improve this answer








                edited 21 mins ago

























                answered 27 mins ago









                igaligal

                5,3161234




                5,3161234






























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