### 14.3 Buffer description

To help hashing non-contiguous areas of memory a general purpose data type is defined:

Data type: gcry_buffer_t ¶

  This type is a structure to describe a buffer. The user should make sure that this structure is initialized to zero. The available fields of this structure are:

  `.size`

    This is either 0 for no information available or indicates the allocated length of the buffer.

  `.off`

    This is the offset into the buffer.

  `.len`

    This is the valid length of the buffer starting at `.off`.

  `.data`

    This is the address of the buffer.