Function fstat() returns information about the file with file descriptor fd. dio_stat() returns an associative array with the following keys:
"device" - device
"inode" - inode
"mode" - mode
"nlink" - number of hard links
"uid" - user id
"gid" - group id
"device_type" - device type (if inode device)
"size" - total size in bytes
"blocksize" - blocksize
"blocks" - number of blocks allocated
"atime" - time of last access
"mtime" - time of last modification
"ctime" - time of last change