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/.qmail dashext.
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)