generate the password databases
style secure and insecure databases for the specified file. These databases
are then installed into /etc/spwd.db
respectively. The file is
installed into /etc/master.passwd
. The file
must be in the correct format (see
It is important to note that the format used in this system is different from
the historic Version 7 style format.
The options are as follows:
- Check if the password file is in the correct format. Do not change, add,
or remove any files.
pwd_mkdb to exit with an error if
it cannot obtain a lock on the file. By default, we block waiting for a
lock on the source file. The lock is held through the rebuilding of the
- Create a Version 7 style password file and install it into
- Ignore locking failure of the
master.passwd file. This option is
intended to be used to build password files in the release process over
NFS where no contention can happen. A non-default directory must also be
specified with the
-d option for
locking to be ignored. Other use of this option is strongly
- Store databases into specified destination directory instead of
- 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
- Specify in megabytes the size of the memory cache used by the hashing
library. On systems with a large user base, a small cache size can lead to
prohibitively long database file rebuild times. As a rough guide, the
memory usage of
pwd_mkdb in megabytes
will be a little bit more than twice the figure specified here. The
default is 2 megabytes.
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
The following options affected the generation of legacy entries, and are now
- Store data in big-endian format.
- Store data in little-endian format.
utility exits zero on success,
non-zero on failure.
will suppress the warning
messages that are normally generated for large user and group IDs. Such IDs
can cause serious problems with software that makes assumptions about the
values of IDs.
- The insecure password database file.
- A temporary file.
- The secure password database file.
- A temporary file.
- The current password file.
- A Version 7 format password file.
Regenerate the password database after manually editing or replacing the
/usr/sbin/pwd_mkdb -p /etc/master.passwd
Previous versions of the system had a program similar to
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.
Because of the necessity for atomic update of the password files,
to install them. This, however, requires that the file specified on the
command line live on the same file system as the
There are the obvious races with multiple people running
on different password files at the
same time. The front-ends to
handle the locking necessary to avoid this problem.