269. Matching Data Representations


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It is the user's responsibility to ensure that the data representation used to read data from a file is compatible with the data representation that was used to write that data to the file.

In general, using the same data representation name when writing and reading a file does not guarantee that the representation is compatible. Similarly, using different representation names on two different implementations may yield compatible representations.

Compatibility can be obtained when ``external32'' representation is used, although precision may be lost and the performance may be less than when ``native'' representation is used. Compatibility is guaranteed using "external32" provided at least one of the following conditions is met.


User-defined data representations may be used to provide an implementation compatiblity with another implementation's ``native'' or ``internal'' representation.


Advice to users.

Section Additional Support for Fortran Numeric Intrinsic Types , page Additional Support for Fortran Numeric Intrinsic Types , defines routines that support the use of matching datatypes in heterogeneous environments and contains examples illustrating their use. ( End of advice to users.)



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