52 struct device {  struct
53     struct device *next;  argument
54     SANE_Device sane;
55     int dn;			/* usb file descriptor */
56     SANE_Byte res[1024];		/* buffer for responses */
57     size_t reslen;		/* response len */
58     SANE_Option_Descriptor opt[NUM_OPTIONS];
59     Option_Value val[NUM_OPTIONS];
60     SANE_Parameters para;
61     SANE_Bool non_blocking;
62     int scanning;			/* scanning is started */
63     int cancel;			/* cancel flag */
64     int state;			/* current state */
65     int reserved;			/* CMD_RESERVE_UNIT */
66     int reading;			/* READ_IMAGE is sent */
68     SANE_Byte *data;		/* postprocessing cyclic buffer 64k */
69     int datalen;			/* how data in buffer */
70     int dataoff;			/* offset of data */
71     int dataindex;		/* sequental number */
79     SANE_Byte *decData;		/* static buffer of POST_DATASIZE bytes */
80     int decDataSize;
81     int currentDecDataIndex;
83     int resolutions;		/* supported resolution bitmask */
84     int compositions;		/* supported image compositions bitmask */
85     int max_len;			/* effective max len for current doc source */
86     int max_win_width;
87     int max_win_len;
88     int max_len_adf;
89     int max_len_fb;
90     int line_order;		/* if need post processing */
91     SANE_Word dpi_list[30];	/* allowed resolutions */
92     int doc_loaded;
94     SANE_Range win_x_range;
95     SANE_Range win_y_range;
98     int win_width;		/* in 1200dpi points */
99     int win_len;
100     double win_off_x;		/* in inches (byte.byte) */
101     double win_off_y;
102     int resolution;		/* dpi indexed values */
103     int composition;		/* MODE_ */
104     int doc_source;		/* document source */
105     int threshold;		/* brightness */
106     int compressionTypes;
107     SANE_Bool compressionEnabled;
110     int blocklen;			/* image data block len (padding incl.) */
134     int (*dev_request)(struct device *dev,  argument