get_table_attribute/3

Availability::- use_module(library(table)).(can be autoloaded)

Fetch attributes of the table. Defined attributes:

`file`	Unify value with the name of the file with which the table is associated.
`field(N)`	Unify value with declaration of n-th (1-based) field.
`field_separator`	Unify value with the field separator character.
`record_separator`	Unify value with the record separator character.
`key_field`	Unify value with the 1-based index of the field that is sorted or fails if the table contains no sorted fields.
`field_count`	Unify value with the total number of columns in the table.
`size`	Unify value with the number of characters in the table-file, not the number of records.
`window`	Unify value with a term `Start-Size`, indicating the properties of the current window.