
                  Attribute File Format



 The libatts.a is used to read and write from attribute files.

 To use the library:
 Include atts.h.
 Call atts_init() to gather index information about the attribute file.
 Then use the read_line_att()  or read_area_att() to get a specific att.

 There are three functions in the library that can write to the attribute file.
 There is a write_att_struct() for writing atts to a file by passing an
 attribute structure.  Write_att() which is passed the information as
 arguments.  write_att_line() is also passed the line coordinates which are used
 to calculate the category location point.

  This is an example of an attribute file.

A     619393.63    3730948.07     3     1
L     619723.63    3730323.07     1     2
L     619393.63    3730948.07     2     3
A     610000.63    3730000.07     1     4

  There is also a short paper that contains every little detail of the
  attribute file format.  There is also a program 't_atts.c' to test the
  library.

