Generate a serial number i.e. the next number in a series.
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 Syntax

        GT_SerialNumber( cAlias , lError )

 Arguments:

      cAlias - Alias of table
      lError - If .T. generate an error message if failed

 Returns:

      The next serial number in the sequence
      -1 if the record could not be locked

 Description:

      Generate a serial number i.e. the next number in a series.
      Assumes that cAlias is a table containing one field - a numeric
      of unspecified name, and only one record.

 Examples:



 Header File: GT_LIB.CH

 Source: SERIALNO.PRG

 Author:  Martin Colloby