You can delete items in this mapping to unset environment variables.

:func:`unsetenv` will be called automatically when an item is deleted from

:data:`os.environ`, and when one of the:meth:`pop` or:meth:`clear` methods is

called.

:data:`os.environ`, and when one of the:meth:`~dict.pop` or

:meth:`~dict.clear` methods iscalled.

..seealso::

associated with the effective user id of the process; the group access

list may change over the lifetime of the process, it is not affected by

calls to:func:`setgroups`, and its length is not limited to 16. The

deployment target value,:const:`MACOSX_DEPLOYMENT_TARGET`,can be

obtained with:func:`sysconfig.get_config_var`.

deployment target valuecan be obtained with

:func:`sysconfig.get_config_var('MACOSX_DEPLOYMENT_TARGET') <sysconfig.get_config_var>`.

..function::getlogin()

Create a filesystem node (file, device special file or named pipe) named

*path*. *mode* specifies both the permissions to use and the type of node

to be created, being combined (bitwise OR) with one of``stat.S_IFREG``,

``stat.S_IFCHR``, ``stat.S_IFBLK``, and``stat.S_IFIFO`` (those constants are

available in:mod:`stat`). For ``stat.S_IFCHR`` and``stat.S_IFBLK``,

*device* defines thenewly created device special file (probably using

to be created, being combined (bitwise OR) with one of:const:`stat.S_IFREG`,

:const:`stat.S_IFCHR`,:const:`stat.S_IFBLK`, and:const:`stat.S_IFIFO`.

For:const:`stat.S_IFCHR` and:const:`stat.S_IFBLK`, *device* defines the

newly created device special file (probably using

:func:`os.makedev`), otherwise it is ignored.

This function can also support:ref:`paths relative to directory descriptors

..function::major(device, /)

Extract the device major number from a raw device number (usually the

:attr:`st_dev` or:attr:`st_rdev` field from:c:struct:`stat`).

:attr:`~stat_result.st_dev` or:attr:`~stat_result.st_rdev` field from:c:struct:`stat`).

..function::minor(device, /)

Extract the device minor number from a raw device number (usually the

:attr:`st_dev` or:attr:`st_rdev` field from:c:struct:`stat`).

:attr:`~stat_result.st_dev` or:attr:`~stat_result.st_rdev` field from:c:struct:`stat`).

..function::makedev(major, minor, /)

..versionchanged::3.8

On Windows, the:attr:`st_mode` member now identifies special

files as:const:`S_IFCHR`,:const:`S_IFIFO` or:const:`S_IFBLK`

as appropriate.

files as:const:`~stat.S_IFCHR`,:const:`~stat.S_IFIFO` or

:const:`~stat.S_IFBLK`as appropriate.

..versionchanged::3.12

On Windows,:attr:`st_ctime` is deprecated. Eventually, it will

..function::abort()

Generate a:const:`SIGABRT` signal to the current process. On Unix, the default

Generate a:const:`~signal.SIGABRT` signal to the current process. On Unix, the default

behavior is to produce a core dump; on Windows, the process immediately returns

an exit code of ``3``. Be aware that calling this function will not call the

Python signal handler registered for:const:`SIGABRT` with

Python signal handler registered for:const:`~signal.SIGABRT` with

:func:`signal.signal`.