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The following example shows how to pass simple types:

The C++ function, RetReal.cc extern "C"

double RetReal (double &x)

{

return (x + 1.0);

}

The Pascal main program, RetRealMain.p

The commands to compile and execute RetReal.cc and RetRealMain.p

program RetRealMain (output); var

r, s: real;

function RetReal (var x: real): real; external C;

begin

r := 2.0;

s := RetReal (r);

writeln ( r: 4: 1,' Return - ', s: 4: 1); end.

hostname% CC -c RetReal.cc hostname% pc RetReal.o RetRealMain.p hostname% a.out

2.0 Return - 3.0

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Pascal 4.0 User’s Guide