Converts the byte array src into a hexadecimal string. If final_len is
greater than -1, the returned string is terminated at that index
(returned_string[final_len] == '\0'),
Parameters
src: string|Uint8Array<ArrayBufferLike>
an array of bytes
final_len: number
an index where to cut off the returned string, or -1
Converts the byte array
srcinto a hexadecimal string. Iffinal_lenis greater than -1, the returned string is terminated at that index (returned_string[final_len] == '\0'),