pwd_mkdb
creates
db(3)
style secure and insecure databases for the specified file.
These databases are then installed into
/etc/spwd.db
and
/etc/pwd.db,
respectively.
The
file
argument is installed into
/etc/master.passwd
by renaming
file.
The
file
must be in the correct format (see
passwd(5/)).
It is important to note that the format used in this system is
different from the historic 6th Edition-style format.
The options are as follows:
-c
Check if the password file is in the correct format.
Do not change, add, or remove any files.
-d directory
Operate in a base directory other than the default of
/etc.
All absolute paths (including
file)
will be made relative to
directory.
Any directories specified as a part of
file
will be stripped off.
This option is used to create password databases in directories
other than
/etc;
for instance in a
chroot(8)
jail.
-p
Create a 6th Edition-style password file and install it into
/etc/passwd.
-s
Only update the secure version of the database.
This is most commonly used in conjunction with the
-u
flag during a password change.
Because the insecure database doesn't contain the password there
is no reason to update it if the only change is in the password field.
Cannot be used in conjunction with the
-p
flag.
-u username
Only update the record for the specified user.
Utilities that operate on a single user can use this option to avoid the
overhead of rebuilding the entire database.
This option must never be used if the line number of the user's record in
/etc/master.passwd
has changed.
file
The absolute path to a file in
master.passwd
format, as described in
passwd(5).
The two databases differ in that the secure version contains the user's
encrypted password and the insecure version has an asterisk
(‘\&*’).
The databases are used by the C library password routines (see
getpwent(3/)).
pwd_mkdb
exits zero on success, non-zero on failure.
Previous versions of the system had a program similar to
pwd_mkdb,
mkpasswd(),
which built
dbm(3)
style databases for the password file but depended on the calling programs
to install them.
The program was renamed in order that previous users of the program
not be surprised by the changes in functionality.
BUGS
Because of the necessity for atomic update of the password files,
pwd_mkdb
uses
rename(2)
to install them.
This, however, requires that the file specified on the command line live
on the same file system as the
/etc
directory.
There are the obvious races with multiple people running
pwd_mkdb
on different password files at the same time.
The front-ends to
pwd_mkdb,
chpass(1),
passwd(1),
and
vipw(8)
handle the locking necessary to avoid this problem.