buffer_getn - read binary data from buffer

       buffer_getn  copies data to x[0], x[1], ..., x[len-1] from the buffer, calling buffer_feed as needed, and
       returns len.

       If a read error occurs, buffer_getn returns -1 and sets errno appropriately.  It may then  have  put  any
       number  between  0  and  len  in the buffer, you can't tell.  That makes this function only useful if you
       don't care when an error occurs.  Use buffer_get otherwise.

       If the read operation signals end-of-file before len bytes were read, buffer_getn returns the  number  of
       bytes read from the buffer before end-of-file.

       buffer_getn - read binary data from buffer

buffer_init(3), buffer_get(3), buffer(3)

                                                                                                  buffer_getn(3)

#include<libowfat/buffer.h>

       ssize_t buffer_getn(buffer* b,char* x,size_t len);