On boost 1.73.0 for linux, I am unable to use group calls like terminate or wait.

Hello, I have noticed on linux I am unable to use group.terminate() or group.wait() with boost 1.73.0. This does work on windows.
~~~
void TestGroupWait(const std::string& cmd1, const std::string& cmd2)
{
bp::ipstream outStream; //reading pipe-stream
bp::ipstream errStream;
std::error_code ec;
std::error_code ec2;

boost::process::group grp;

bp::child childProc(cmd1, bp::std_out > outStream, bp::std_err > errStream, ec);
bp::child ChildProc2(cmd2, ec2);
grp.add(childProc, ec);
grp.add(ChildProc2, ec2);
grp.wait();
childProc.exit_code();
ChildProc2.exit_code();
}
void TestGroupKill(const std::string& cmd1, const std::string& cmd2)
{
bp::ipstream outStream; //reading pipe-stream
bp::ipstream errStream;
std::error_code ec;
std::error_code ec2;

boost::process::group grp;

bp::child childProc(cmd1, bp::std_out > outStream, bp::std_err > errStream, ec);
bp::child ChildProc2(cmd2, ec2);
grp.add(childProc, ec);
grp.add(ChildProc2, ec2);
grp.terminate();
}
~~~

When I call grp.terminate I get an exception:

terminate called after throwing an instance of 'boost::process::process_error'
what(): killpg(2) failed in terminate: Invalid argument

Its a similar error for grp.wait().

If I put out the native_handle on group, I see that linux is returning -1 for the group handle. I think that is why it is throwing.