• A line beginning with the character # is a comment.

• A line not beginning with the character # is of the form:

◦ level field value

◦ where:

◦ level is an integer

◦ field is a name

◦ value is a string that can be present

• A field must be one of the following:

◦ The name of a simple data type (integer, string, real, and so on)

◦ The name of an array

◦ The name of a structure

◦ The name of a pointer to a structure

• All the fields on a particular level belong to the same parent.

• When value is present at a certain level and begins with the left square bracket character ([), or consists of a series of digits separated by commas, it indicates that field is an array of dimension [n]([m] ...). The array element values are contained on the lines level+1 up to the next line starting with level again.

◦ For one-dimensional arrays, only one line is at the higher level whose value is a string of element values separated by commas.

◦ The notation< n*m> indicates the following <n> elements each have the value <m>.

• When value is present at a certain level (and is not the string ->), this is the value to be assigned to field.

• When value is absent at a certain level, this indicates that field is a structure. Immediate elements of the aggregate are contained on lines level+1 up to next line starting with level again.

• The line whose field is the string ugc_xar_len is a special case indicating that the next line begins the description of an array of length value.

• When value is the string ->, this indicates that field is a pointer to an aggregate whose elements follow.

• The special value string NULL indicates that the field is a pointer whose value is null.