@subheading asn1_bit_der
@anchor{asn1_bit_der}
@deftypefun {void} {asn1_bit_der} (const unsigned char * @var{str}, int @var{bit_len}, unsigned char * @var{der}, int * @var{der_len})
@var{str}: BIT string.

@var{bit_len}: number of meaningful bits in STR.

@var{der}: string returned.

@var{der_len}: number of meaningful bytes of DER
(der[0]..der[ans_len-1]).

Creates a length-value DER encoding for the input data
as it would have been for a BIT STRING.
The DER encoded data will be copied in @code{der}.

Note that the BIT STRING tag is not included in the output.

This function does not return any value because it is expected
that @code{der_len} will contain enough bytes to store the string
plus the DER encoding. The DER encoding size can be obtained using
@code{asn1_length_der()}.
@end deftypefun

