Brett Cannon added the comment: os.chmod is implemented in posixmodule.c and the argument parsing code can be found at http://hg.python.org/cpython/file/3acbb23c73bc/Modules/posixmodule.c#l2605 . You will notice that the argument parsing is specified as "O&i|$O&p". That means the first argument is parsed as a Python object which is passed through a converter function and the second argument is required to be an integer. That converter function can be found at http://hg.python.org/cpython/file/3acbb23c73bc/Modules/posixmodule.c#l681. Looking at that code doesn't suggest that TypeError is raised with that message. What were the exact arguments you passed into os.chmod() that triggered the exception? ---------- assignee: docs@python -> components: +Library (Lib) -Documentation nosy: +brett.cannon status: open -> pending versions: -Python 2.6, Python 2.7, Python 3.1, Python 3.2, Python 3.3, Python 3.5 _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue18269> _______________________________________

Brett Cannon added the comment: That's expected with that kind of argument. os.fchmod() and os.chmod() only accept a path as a string or a file descriptor as an integer as specified in the docs: http://docs.python.org/3/library/os.html#os.chmod ---------- resolution: -> invalid status: open -> closed _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue18269> _______________________________________

Brett Cannon added the comment: That is not a documentation bug (i.e. a problem with what is written at docs.python.org), this is a feature request to try to improve the exception message. That would require adding a new parameter format (http://docs.python.org/3/c-api/arg.html?highlight=pyarg_parse#other-objects) which allows for a converter function which also takes the positional number and/or keyword argument that the converter function was called for. ---------- assignee: docs@python -> components: +Interpreter Core -Documentation, Library (Lib) priority: normal -> low title: Clarify which integer is required in os.chmod() exception -> Add new parameter format for converter function w/ position number type: -> enhancement versions: -Python 2.7, Python 3.3 _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue18269> _______________________________________

Ronald Oussoren added the comment: I don't think that a new parameter format is sufficient. For the message in this call the new parameter isn't even needed, you'd "just" have to ensure that enough information is available in convertsimple to create a more useful message. That said, that is far from a trivial change, more so because the PyArg_Parse family of functions can parse fairly complicated argument structures in one go (such as using ``PyArg_Parse(args, "(si)", &host, port)`` to unpack the tuple in the first (and only) argument). ---------- nosy: +ronaldoussoren _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue18269> _______________________________________