Power assertion example

gistfile1.m

// Begin the power assertion
IOPMAssertionID assertionID;
IOReturn asserted = IOPMAssertionCreateWithName(kIOPMAssertionTypeNoIdleSleep,
                                                kIOPMAssertionLevelOn,
                                                CFSTR("Sandvox Publishing"),
                                                &assertionID);
if (asserted != kIOReturnSuccess) // handle the error; log it or something

// Do your long-running work

// End the power assertion
if (asserted == kIOReturnSuccess)
{
    asserted = IOPMAssertionRelease(assertionID);
    if (asserted != kIOReturnSuccess) // handle the error; log it or something
}