=head1 NAME
BN_set_bit, BN_clear_bit, BN_is_bit_set, BN_mask_bits, BN_lshift,
-BN_lshift1, BN_rshift, BN_rshift1 - Bit operations on BIGNUMs
+BN_lshift1, BN_rshift, BN_rshift1 - bit operations on BIGNUMs
=head1 SYNOPSIS
number is expanded if necessary.
BN_clear_bit() sets bit B<n> in B<a> to 0 (C<a&=~(1E<lt>E<lt>n)>). An
-error occurs it B<a> is shorter than B<n> bits.
+error occurs if B<a> is shorter than B<n> bits.
BN_is_bit_set() tests if bit B<n> in B<a> is set.
BN_mask_bits() truncates B<a> to an B<n> bit number
-(C<q&=~((~0)E<gt>E<gt>n)>). An error occurs it B<a> already is
+(C<a&=~((~0)E<gt>E<gt>n)>). An error occurs if B<a> already is
shorter than B<n> bits.
BN_lshift() shifts B<a> left by B<n> bits and places the result in
B<r> (C<r=a/2^n>). BN_rshift1() shifts B<a> right by one and places
the result in B<r> (C<r=a/2>).
+For the shift functions, B<r> and B<a> may be the same variable.
+
=head1 RETURN VALUES
BN_is_bit_set() returns 1 if the bit is set, 0 otherwise.