forlang.hlp (Table of Contents; Topic list)
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COMMON
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─────COMMON─────────────────────────────────────────────────────────────────
 
     Action
 
     Shares variables between two or more program units.
 
     Syntax
 
     COMMON [/[cname] [ [attrs] ]/] nlist [ [,]/[cname][attrs]/nlist ]...
 
     Parameter          Description
 
     cname              A name for the common block.
 
     [attrs]            A list of attributes, separated by commas.
                        Valid attributes are: ALIAS, C, FAR, NEAR,
                        and PASCAL.
 
     nlist              A list of variable names, array names, and
                        array declarators, separated by commas.
 
                        Formal-argument names, function names,
                        automatic variables, and allocatable arrays
                        cannot appear in a COMMON statement.
 
     Remarks
 
     A common block can appear more than once in the same program
     unit. If two common blocks have the same name, the second is
     treated as a continuation of the first.
 
     The length of a common block equals the number of bytes required
     to hold all elements in that common block. If several program
     units refer to the same named common block, the common block must
     be the same length in each program unit. The blank common block
     can have a different length in different program units.
 
     Example
 
           PROGRAM MyProg
           COMMON i, j, x, k(10)
           COMMON /mycom/ a(3)
           .
           .
           .
           END
 
           SUBROUTINE MySub
           COMMON pe, mn, z, idum(10)
           COMMON /mycom/ a(3)
           .
           .
           .
           END
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