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qmail-getpw(8)


NAME

   qmail-getpw - give addresses to users

SYNOPSIS

   qmail-getpw local

DESCRIPTION

   In  qmail,  each user controls a vast array of local addresses.  qmail-
   getpw finds the user that controls a  particular  address,  local.   It
   prints  six  pieces  of information, each terminated by NUL: user; uid;
   gid; homedir; dash; and ext.  The user's  account  name  is  user;  the
   user's  uid  and  gid  in  decimal  are  uid  and  gid; the user's home
   directory is  homedir;  and  messages  to  local  will  be  handled  by
   homedir/.qmaildashext.

   In   case  of  trouble,  qmail-getpw  exits  nonzero  without  printing
   anything.

   WARNING: The operating system's getpwnam  function,  which  is  at  the
   heart of qmail-getpw, is inherently unreliable: it fails to distinguish
   between temporary errors and nonexistent  users.   Future  versions  of
   getpwnam  should  return ETXTBSY to indicate temporary errors and ESRCH
   to indicate nonexistent users.

RULES

   qmail-getpw considers an account in /etc/passwd to be a user if (1) the
   account has a nonzero uid, (2) the account's home directory exists (and
   is  visible  to  qmail-getpw),  and  (3)  the  account  owns  its  home
   directory.   qmail-getpw  ignores  account  names  containing uppercase
   letters.  qmail-getpw also assumes that all account names  are  shorter
   than 32 characters.

   qmail-getpw gives each user control over the basic user address and all
   addresses of the form user-anything.  When local is user, dash and  ext
   are  both empty.  When local is user-anything, dash is a hyphen and ext
   is anything.  user may appear  in  any  combination  of  uppercase  and
   lowercase letters at the front of local.

   A  catch-all  user,  alias, controls all other addresses.  In this case
   ext is local and dash is a hyphen.

   You can override all of qmail-getpw's decisions  with  the  qmail-users
   mechanism, which is reliable, highly configurable, and much faster than
   qmail-getpw.

SEE ALSO

   qmail-users(5), qmail-lspawn(8)

                                                            qmail-getpw(8)



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