Random bitstring generation in PARI library

[Aleksandr Lenin <aleksandr.lenin@cyber.ee>]

Hello,

what is the procedure to generate a random k-bit number, where k is
greater than BITS_IN_LONG?

Reading through the manual
(https://pari.math.u-bordeaux.fr/pub/pari/manuals/2.10.0/libpari.pdf) I
managed to find only pari_rand, random_bits, random_Fl which return an
(unsigned) long, and I need a bigger number. The function randomi indeed
returns a GEN, but in the range 1..p-1, but I need a random bitstring of
length k.

Could you please recommend any procedure how to accomplish this task in
PARI library?

-- 
With kind regards,
Aleksandr