Technical Reference: Base Operating System and Extensions, Volume 1

pm_battery_control Subroutine

Purpose

Controls and queries the battery status.

Library

Standard C Library (libc.a)

Syntax

#include <sys/pm.h>
 
int pm_battery_control(Command, Battery);
int Command;
struct pm_battery *Battery;

Description

The pm_battery_control subroutine controls and queries the battery status.

Parameters

Command

Specifies one of the following:

PM_BATTERY_DISCHARGE: Discharges the battery.
PM_BATTERY_QUERY: Queries fuel state of the battery.

Battery

Points a following pm_battery structure to return battery information. When Command is PM_BATTERY_QUERY, the following structure is used:

struct pm_battery {
   int  attribute;/*battery attributes are as follows*/
         PM_BATTERY  /* battery is supported */
         PM_BATTERY_EXIST    /* battery exists */
         PM_NICD      /*NiCd or NiMH */
         PM_CHARGE   /* now charging */
         PM_DISCHARGE   /* now discharging */
         PM_AC       /* AC power is in use */
         PM_DC       /* DC power is in use */
   int capacity;   /* battery capacity */
   int remain;   /* current remaining capacity */
   int discharge_remain;
         /*remaining capacity while discharging */
   int  discharge_time;   /* discharge time */
   int  full_charge_count; /*full charge count */
}
If a field is not applicable, -1 is set.

Return Values

PM_SUCCESS	Indicates successful completion.
PM_ERROR	Indicates an error condition. The variable errno is set to identify the error.

Error Codes

EINVAL

The argument or command is not valid.

Implementation Specifics

The pm_battery_control subroutine is part of the Base Operating System (BOS) Runtime.

Related Information

The pm_control_state (pm_control_state Subroutine) subroutine, pm_control_parameter (pm_control_parameter Subroutine) subroutine.