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Namespaces

.. py:currentmodule:: lxns.namespaces

Namespace is an isolation mechanism. In total there are 7 different namespace types each representing a certain operating system domain.

For example, :py:class:`MountNamespace` allows to creating new mount points without affecting other processes.

Namespace classes should not be initialized directly. Instead either :py:meth:`BaseNamespace.from_pid` or :py:meth:`BaseNamespace.from_self` class methods should be used to create a namespace object which represents a reference to an existing namespace.

An existing namespace can be entered using :py:meth:`BaseNamespace.setns`. A new namespace can be created using :py:meth:`BaseNamespace.unshare` class method or :py:meth:`unshare_namespaces` function.

File descriptors are a limited resource and every namespace reference requires one. Because of this a warning will be emitted if a namespace object was deallocated without closing the file descriptor. To avoid this use :py:meth:`BaseNamespace.close` or a with block. For example:

from lxns.namespaces import UserNamespace

with UserNamespace.from_pid(123456) as user_ns:
    user_ns.setns()

# Inside the user namespace

Namespace object cannot be used after it was closed and all methods will raise ValueError.

All namespace classes implement similar API and only differ in the type of namespace they reference. For brevity only :py:class:`BaseNamespace` has the methods documented.

.. autoclass:: lxns.namespaces.BaseNamespace
    :members: __init__, fileno, setns, get_user_namespace, close, from_pid, from_self,
              get_current_ns_id, unshare, ns_id, get_current_limit, set_current_limit


.. autoclass:: lxns.namespaces.UserNamespace

    Implements same API as :py:class:`BaseNamespace`.


.. autoclass:: lxns.namespaces.MountNamespace

    Implements same API as :py:class:`BaseNamespace`.


.. autoclass:: lxns.namespaces.NetworkNamespace

    Implements same API as :py:class:`BaseNamespace`.


.. autoclass:: lxns.namespaces.IpcNamespace

    Implements same API as :py:class:`BaseNamespace`.


.. autoclass:: lxns.namespaces.CgroupNamespace

    Implements same API as :py:class:`BaseNamespace`.


.. autoclass:: lxns.namespaces.PidNamespace

    Implements same API as :py:class:`BaseNamespace`.


.. autoclass:: lxns.namespaces.TimeNamespace

    Implements same API as :py:class:`BaseNamespace`.


.. autoclass:: lxns.namespaces.UtsNamespace

    Implements same API as :py:class:`BaseNamespace`.


.. autodata:: lxns.namespaces.ALL_NAMESPACE_CLASSES
    :annotation:


.. autofunction:: lxns.namespaces.unshare_namespaces