- along with this program; if not, write to the Free Software
- Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
- 02110-1301, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
+
+/* Infrastructure common to system file reader and writer.
+
+ Old versions of SPSS limited string variables to a width of
+ 255 bytes. For backward compatibility with these older
+ versions, the system file format represents a string longer
+ than 255 bytes, called a "very long string", as a collection
+ of strings no longer than 255 bytes each. The strings
+ concatenated to make a very long string are called its
+ "segments"; for consistency, variables other than very long
+ strings are considered to have a single segment.
+
+ The interfaces in this file primarily provide support for
+ dealing with very long strings. */