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FILEMAP Directive

A Fortran file is an infinite one-dimensional array of records, with LB=1. A filemap can be thought of as an assumed-size array of records. This array is associated with (one-dimensional) files, using storage association rules. The filemap name is used to specify a mappings for files. The association between a filemap name and an actual file is effected by the OPEN statement.

A FILEMAP directive declares filemap names. The syntax is

XBNF filemap-directive -to -rule to to is FILEMAP [::] filemap-name ( assumed-size-spec ) [, filemap-name (assumed-size-spec ) ] ... -to or FILEMAP, DIMENSION ( assumed-size-spec ) :: filemap-name-list XBNF

An assumed-size-spec is a specification of the form used for assumed sized arrays: All dimensions are specified, with the exception of the last, which is assumed. In our case, the last dimension is infinite. Only initialization expressions may occur in this specification (including expressions that depend on NUMBER_OF_IONODES).

For example:

!HPF FILEMAP, DIMENSION(2,2,1:*) :: F2,F3 A FILEMAP directive does not allocate space, neither in memory, nor on disk.
Thu May 5 15:11:02 CDT 1994