rlib/test/test_rsocket.py::test_sethostname

@pytest.mark.skipif(sys.platform == "win32",
            reason='No sethostname on Windows')
    @pytest.mark.skipif(not hasattr(os, 'geteuid') or os.geteuid() == 0,
            reason='Running as superuser is not supported.')
    def test_sethostname():
        # just in case it worked anyway, use the old hostname
>       s = gethostname()

rlib/test/test_rsocket.py:774: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
rlib/rsocket.py:1575: in gethostname
    res = _c.gethostname(buf, size)
rtyper/lltypesystem/rffi.py:321: in wrapper
    res = call_external_function(*real_args)
<46-codegen /workspace/rpython/rtyper/lltypesystem/rffi.py:217>:13: in call_external_function
    res = funcptr(a0, a1)
rtyper/lltypesystem/lltype.py:1384: in __call__
    return callb(*args)
rtyper/lltypesystem/ll2ctypes.py:1342: in __call__
    return self.trampoline(*argvalues)
rtyper/lltypesystem/ll2ctypes.py:1374: in invoke_via_ctypes
    cres = callme(cargs)
rtyper/lltypesystem/ll2ctypes.py:1360: in callme
    return cfunc(*cargs)
/opt/pypy2.7-v7.3.22-linux64/lib_pypy/_ctypes/function.py:354: in __call__
    self._convert_args(argtypes, args, kwargs))
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

self = <ctypes._FuncPtr object at 0x000000002646b7f0>
argtypes = [<class '_ctypes.pointer.LP_ctypes_Array of Char {'nolength': True} *0'>, <class 'ctypes.c_int'>]
args = (<_ctypes.pointer.LP_ctypes_Array of Char {'nolength': True} *0 object at 0x0000000034838e18>, 1024L)
kwargs = {}, marker = <object object at 0x00000000226f3430>

    def _convert_args(self, argtypes, args, kwargs, marker=object()):
        newargs = []
        outargs = []
        keepalives = []
        newargtypes = []
        total = len(args)
        paramflags = self._paramflags
    
        if not paramflags and total < len(argtypes):
            raise TypeError("not enough arguments")
    
        if paramflags:
            errcheckargs = []
            inargs_idx = 0
            for i, argtype in enumerate(argtypes):
                flag = 0
                defval = marker
                paramflag = paramflags[i]
                paramlen = len(paramflag)
                name = None
                if paramlen == 1:
                    flag = paramflag[0]
                elif paramlen == 2:
                    flag, name = paramflag
                elif paramlen == 3:
                    flag, name, defval = paramflag
                flag = flag & PARAMFLAG_COMBINED
                if flag == PARAMFLAG_FIN | PARAMFLAG_FLCID:
                    val = defval
                    if val is marker:
                        val = 0
                    errcheckargs.append(val)
                    keepalive, newarg, newargtype = self._conv_param(argtype, val)
                    keepalives.append(keepalive)
                    newargs.append(newarg)
                    newargtypes.append(newargtype)
                elif flag in (0, PARAMFLAG_FIN):
                    if inargs_idx < total:
                        val = args[inargs_idx]
                        inargs_idx += 1
                    elif kwargs and name in kwargs:
                        val = kwargs[name]
                        inargs_idx += 1
                    elif defval is not marker:
                        val = defval
                    elif name:
                        raise TypeError("required argument '%s' missing" % name)
                    else:
                        raise TypeError("not enough arguments")
                    errcheckargs.append(val)
                    keepalive, newarg, newargtype = self._conv_param(argtype, val)
                    keepalives.append(keepalive)
                    newargs.append(newarg)
                    newargtypes.append(newargtype)
                elif flag == PARAMFLAG_FOUT:
                    if defval is not marker:
                        val = defval
                        keepalive, newarg, newargtype = self._conv_param(argtype, defval)
                    else:
                        import ctypes
                        val = argtype._type_._newowninstance_()
                        keepalive = None
                        newarg = ctypes.byref(val)
                        newargtype = type(newarg)
                    errcheckargs.append(val)
                    outargs.append(val)
                    keepalives.append(keepalive)
                    newargs.append(newarg)
                    newargtypes.append(newargtype)
                else:
                    raise ValueError("paramflag %d not yet implemented" % flag)
        else:
            errcheckargs = args
            for i, argtype in enumerate(argtypes):
                try:
                    keepalive, newarg, newargtype = self._conv_param(argtype, args[i])
                except (UnicodeError, TypeError, ValueError) as e:
>                   raise ArgumentError(str(e))
E                   ArgumentError: expected LP_ctypes_Array of Char {'nolength': True} *0 instance instead of LP_ctypes_Array of Char {'nolength': True} *0

/opt/pypy2.7-v7.3.22-linux64/lib_pypy/_ctypes/function.py:589: ArgumentError

builder: rpython-linux-x86-64 build #716*

test: rlib/test/test_rsocket.py::test_sethostname