Advanced Power Management (APM) support has been in the kernel since 1.3.46.
On laptop computers, the APM support provides access to battery status
information and may help you to conserve battery power, depending on your
laptop and the APM implementation.

The apmd-2.1 package provides:
    1) a new apmd(8) to provide logging of the battery status
    2) an apm(1) utility to print /proc/apm
    3) an xapm(1x) utility to provide a little graph in X
    4) a libapm.a for writing similar applications

The apmd-2.2 package provides:
    Support for /dev/apm_bios (10,134) which should appear in 1.3.85.
    In previous kernels, the apm_bios device was dynamically allocated.
    The apm(1) and xapm(1x) from apmd-2.1 will continue to work with these
    newer kernels, but apmd(8) will fail.  The new apmd-2.2 utilities will
    work with older and newer kernels, so please upgrade to apmd-2.2 even
    if you use an older kernel.

The apm-2.4 package provides:
    Support for putting he machine into standby and suspend modes
    using the -S and -s switches to the apm program.

All of these utilities should work with both the old (pre-1.3.58) and the
new (1.3.58) /proc/apm format.  No further changes in the /proc/apm format
are anticipated.
