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 Using COMMON with CHAIN
 
 ■ The COMMON statement provides the only way to pass variable values
   directly to a chained program.
 
 ■ To pass variables, both programs must contain COMMON statements. Note:
   Variable order and type are significant, not variable names.
 
 ■ The order and type of variables must be the same for all COMMON statements
   communicating between chaining programs.
 
 ■ Although the order and type of variables is critical for ensuring that
   the right values are passed, COMMON blocks do not have to be the same
   size.
 
 ■ If the COMMON block in the chained-to program is smaller than the COMMON
   block in the chaining program, the extra COMMON variables in the chaining
   program are discarded.
 
 ■ If the size of the COMMON block in the chained-to program is larger than
   the COMMON block in the chaining program, then:
   • Additional COMMON numeric variables are initialized to zero
   • Additional string variables are initialized to null strings
 
 ■ Static arrays passed in a COMMON block by the chaining program must be
   declared as static in the chained-to program. Similarly, dynamic arrays
   placed in COMMON by the chaining program must be dynamic in the chained-
   to program.
 
 See: ◄COMMON Statement►  ◄Scope Rules►