HPF can call procedures written in other languages or other parallel programming styles. These are called EXTRINSIC procedures.
An INTERFACE including mapping information must be given:
INTERFACE
EXTRINSIC (C) SUBROUTINE Job(a)
REAL, DIMENSION(:) :: a
!HPF$ DISTRIBUTE a(BLOCK)
END SUBROUTINE Job
END INTERFACE
this would correspond to a C void function with a single array argument.
It is up to the compiler to decide which languages are supported.
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