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─────BLOCK DATA ────────────────────────────────────────────────────────────
 
     Action
 
     Identifies a block-data subprogram, where variables and array
     elements in named common blocks can be initialized.
 
     Syntax
 
     BLOCK DATA [blockdataname]
 
     Parameter          Description
 
     blockdataname      A unique global name for the subprogram.
 
     Remarks
 
     The BLOCK DATA statement must be the first statement in a
     block-data subprogram.
 
     Only one unnamed block-data subprogram may appear in an
     executable program.
 
     The following restrictions apply:
 
       ■ The only statements that may be used in a block-data
         subprogram are BLOCK DATA, COMMON, DATA, DIMENSION, END,
         END MAP, END STRUCTURE, END UNION, EQUIVALENCE, IMPLICIT,
         MAP, PARAMETER, RECORD, SAVE, STRUCTURE, UNION, and type
         statements. No executable statements are permitted.
 
       ■ Only an entity defined in a named common block may be initially
         defined in a block-data subprogram.
 
       ■ All the constituents of a named common block must be specified
         in that block-data subprogram, even if not all of the
         constituents are initialized.
 
     Examples
 
     C     The following block-data subprogram initializes
     C     the named common block /greatlakes/:
     C
 
           INTEGER*2 erie, huron, michigan, ontario, superior
           BLOCK DATA Lakes
           COMMON /greatlakes/ erie, huron, michigan, ontario, superior
           DATA erie, huron, michigan, ontario, superior /1, 2, 3, 4, 5/
           END
     C
     C     Using the same common block, /greatlakes/, the
     C     following block-data subprogram is NOT allowed;
     C     not all the members of /greatlakes/ are specified.
 
           BLOCK DATA GrLaks
           COMMON /greatlakes/ erie, huron, ontario, superior
           DATA erie, huron, ontario, superior /1, 2, 4, 5/
           END
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