Swift sysctl获取整数

import Darwin

func getSysctlValue<T>(_ name: String) -> T? {
    var value: T?
    var size = MemoryLayout<T>.size
    
    // Convert name to C string
    let nameCString = name.cString(using: .utf8)
    
    // Call sysctl with NULL value and size to get required buffer size
    sysctlbyname(nameCString, nil, &size, nil, 0)
    
    // Allocate buffer with required size
    let buffer = UnsafeMutablePointer<T>.allocate(capacity: size)
    
    // Call sysctl again with allocated buffer to get the value
    if sysctlbyname(nameCString, buffer, &size, nil, 0) == 0 {
        value = buffer.pointee
    }
    
    // Deallocate buffer
    buffer.deallocate()
    
    return value
}

// Usage example
if let maxFiles = getSysctlValue("kern.maxfiles") as Int? {
    print("Maximum files: \(maxFiles)")
} else {
    print("Failed to get maximum files")
}