Spanned records

A spanned record is opened using both V and S in the format specifier. A spanned record is a variable-length record in which the length of the record can exceed the size of a block. If it does, the record is divided into segments and accommodated in two or more consecutive blocks. The use of spanned records allows you to select a block size, independent of record length, that will combine optimum use of auxiliary storage with the maximum efficiency of transmission.

VS-format specifies that each block contains only one record or segment of a record. The first 4 bytes of a block describe the block control information. The second 4 bytes contain record or segment control information, including an indication of whether the record is complete or is a first, intermediate, or last segment.

VBS-format differs from VS-format in that each block in VBS-format contains as many complete records or segments as it can accommodate, while each block in VS-format contains at most one record per block.