pwconv - install and update /etc/shadow with information from /etc/passwd
The pwconv command creates and updates /etc/shadow with information from
If the /etc/shadow file does not exist, pwconv creates /etc/shadow with
information from /etc/passwd. The command populates /etc/shadow with the
user's login name, password, and password aging information. If password
aging information does not exist in /etc/passwd for a given user, none is
added to /etc/shadow. However, the last changed information is always
If the /etc/shadow file does exist, the following tasks are performed:
o Entries that are in the /etc/passwd file and not in the /etc/shadow
file are added to the /etc/shadow file.
o Entries that are in the /etc/shadow file and not in the /etc/passwd
file are removed from /etc/shadow.
o Password attributes (for example, password and aging information) in
an /etc/passwd entry are moved to the corresponding entry in
The pwconv program is a privileged system command that cannot be executed
by ordinary users.
The contents of the /etc/passwd and /etc/shadow files are saved in
/etc/opasswd and /etc/oshadow, respectively. The system can be restored
to its preconversion state by replacing the content of the /etc/passwd
file with the content of /etc/opasswd and removal of /etc/shadow (if it
did not exist prior to the run of pwconv) or its replacement by
/etc/oshadow. These files are overwritten each time the pwconv program
is run. The use of some of the system administration tools causes pwconv
to be run, and therefore the backup files to be overwritten, each time an
entry is added, deleted, or modified.
pwconv does not copy NIS entries from /etc/passwd. However, a shadow file
can be served by NIS using nsd (see shadow(4)).
The pwconv command exits with one of the following values:
1 Permission denied.
2 Invalid command syntax.
3 Unexpected failure. Conversion not done.
4 Unexpected failure. Password file(s) missing.
5 Password file(s) busy. Try again later.
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