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=head1 NAME

tpm_nvread

=head1 SYNOPSIS

B<tpm_nvread [OPTIONS]>

=head1 DESCRIPTION

B<tpm_nvread> reads data from an NVRAM area and either displays them or writes
them into a file. The user must provide the index of the NVRAM area. If the
user provided the number of bytes to read then this will be the maximum
number of bytes that will be read from the NVRAM area, otherwise the whole
NVRAM area will be read. Some NVRAM areas only allow read sizes of zero,
i.e., NVRAM area index 0. Optionally an offset into the NVRAM
area can be given where the reading of the data is to start. If the NVRAM
area has permission bits set that require owner or NVRAM area authentication,
then the password must be provided via the password option.

The following options are supported:

=over 4

=item B<-h, --help>

Display command usage info.

=item B<-v, --version>

Display command version info.

=item B<-l, --log [none|error|info|debug]>

Set logging level.

=item B<-u, --unicode>

Use TSS UNICODE encoding for passwords to comply with applications
using TSS popup boxes

=item B<-z, --well-known>

Use a secret of all zeros (20 bytes of zeros) as either the NVRAM area or owner secret.

=item B<-p, --password>

Depending on what type of authentication is required for the NVRAM area, this must either
be the NVRAM area or owner password.

A password may be directly provided for example by using '--password=password' or
'-ppassword'. If no password is provided then the program will prompt the user for the
password.

=item B<-i, --index>

The index of the NVRAM area.
The parameter may either be a decimal number or a hexadecimal number starting with '0x'.

=item B<-s, --size>

The number of bytes to read from the NVRAM area.
The parameter may either be a decimal number or a hexadecimal number starting with '0x'.

=item B<-n, --offset> (optional parameter)

The offset into the NVRAM area from where to start reading.
The parameter may either be a decimal number or a hexadecimal number starting with '0x'.

=item B<-f, --filename> (optional parameter)

The name of a file the read data will be written into. If no filename is
given the data will be printed to stdout.


=back

=head1 SEE ALSO

B<tpm_nvdefine>(8), B<tpm_nvinfo>(8), B<tpm_nvrelease>(8), B<tpm_nvwrite>(8)

=head1 REPORTING BUGS

Report bugs to <trousers-users@lists.sourceforge.net>