sysctlbyname() On FreeBSD

[Carpetsmoker]

I recently bought a Thinkpad T61 (Didn't go for the Dell Vermaden), but all battery indicators I could find for FreeBSD eiter do not work, or don't work as I want them to, creating a simple tray application is simple, but I'm having problems with getting the sysctl.

From the commandline:
% sysctl hw.acpi.battery.life
hw.acpi.battery.life: 99

99% means its full, so now from python, from an example found here:

def CheckBatt(tray):
        libc = ctypes.CDLL('libc.so')
        size = ctypes.c_uint(0)
        #libc.sysctlbyname("hw.acpi.battery.life", None, ctypes.byref(size), None, 0) 
        buf = ctypes.create_string_buffer(size.value)
        libc.sysctlbyname("hw.acpi.battery.life", buf, ctypes.byref(size), None, 0)

        print buf.value
        return True

output: `c'

Hm, maybe something went wrong with ctypes? Lets try from C:

#include <stdio.h>
#include <sys/types.h>
#include <sys/sysctl.h>

int
main()
{
        size_t size;
        int buf;
        size = sizeof buf;

        sysctlbyname("hw.acpi.battery.life", &buf, &size, NULL, 0);

        printf("`%s'\n", &buf);
        return 0;
}

Output: `c' ... So the problem isn't in ctypes, but probably in my use of sysctlbyname() (?)

I am not an experienced C programmer, I usually stick to stuff like python, I'm probably doing something stupid, but I can't figure out what.

Also, why does the python example linked above use two sysctlbyname() calls? It seems redundant to me...