Function: auto-compression-mode

Toggle Auto Compression mode.
With a prefix argument ARG, enable Auto Compression mode if ARG
is positive, and disable it otherwise. If called from Lisp,
enable the mode if ARG is omitted or nil.

Auto Compression mode is a global minor mode. When enabled,
compressed files are automatically uncompressed for reading, and
compressed when writing.

Variable: auto-compression-mode

Non-nil if Auto-Compression mode is enabled.
See the command `auto-compression-mode' for a description of this minor mode.
Setting this variable directly does not take effect;
either customize it (see the info node `Easy Customization')
or call the function `auto-compression-mode'.