[nobody@nowhere]$ cat t.cpp
#include <iostream>
using namespace std;
int main() {
    cout << "C++ retVal: 3" << endl;
    return 3;
}

[nobody@nowhere]$ cat t.pl
#!/usr/bin/perl
system("./a.out");
printf "Got retval: %d\n", $?>>8;

[nobody@nowhere]$ ./t.pl
C++ retVal: 3
Got retval: 3

[nobody@nowhere]$
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