=head1 RETURN VALUES

Upon successful completion, a value of B<0> (B<XER_OK>) is returned.
Otherwise, one of the following error codes is returned:

=over 5

=item *

B<1 => B<XER_Usage>

=item *

B<2 => B<XER_BootStrap>

=item *

B<3 => B<XER_ProcessArguments>

=item *

B<4 => B<XER_PayloadSigningError>

=item *

B<5 => B<XER_SignatureVerificationFailed>

=item *

B<6 => B<XER_SignatureVerificationError>

=item *

B<7 => B<XER_RunMode>

=item *

B<8 => B<XER_Shutdown>

=item *

B<9 => B<XER_KeyGenerationError>

=item *

B<10 => B<XER_PasswordGenerationError>

=item *

B<11 => B<XER_SignatureVerificationMixed>

=back

For signature verification operations, a value of B<XER_OK> means that
all specified signatures have been positively verified, a value of
B<XER_SignatureVerificationFailed> means that no matching certificate
was found or the signature is invalid for one or more of the specified
signatures, value of B<XER_SignatureVerificationError> means that a
fatal processing or certificate error was encountered for one or more
of the specified signatures, and a value of
B<XER_SignatureVerificationMixed> means that there were both invalid
signatures and fatal errors.

The output produced by B<WebJob-DsvTool> for a valid signature looks
like this:

    Signature is valid. CommonName = [<name>]

The output produced by B<WebJob-DsvTool> for an invalid signature
looks like this:

    Signature verification failed.

