The following example shows a partial Fortran routine that calls a C function. The called C routine contains the #pragma linkage directive for the C function CFCN and the function definition for the C function.

INTEGER*4 INDEX
REAL*8 LIST(0:99)
REAL*8 VALUE
REAL*8 CFCN
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VALUE=CFCN(INDEX, LIST)
 

#pragma linkage (cfcn, FORTRAN)
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double cfcn(int *index, double list [])
{
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}