fping crashes with __darwin_check_fd_set_overflow. Please help to resolve the issue. about fping

[auerswal]

Please provide additional details about your use of fping.

[Karthikeyan1108]

Hi @auerswal

Thank you for the reply. Please find the usage of fping in the following code. Passing array of hosts to the ping operation in the background queue async way with arguments as below.

`/// Send ping with completion block.
///
/// - Parameters:
/// - hosts: hosts
/// - backoff: default 1.5
/// - count: number of ping send per host
/// - completion: results dictionary, the key is host string, the value is PngResult struct

public static func ping(hosts: [String], backoff: Float = 1.5, count: Int = 1,
                        progress: ((_ progress: (Float)) -> Void)? = nil,
                        completion: @escaping (_ results: [String: PngResult]) -> Void) {

    let argv:[String?] = ["", "-c\(count)", "-B\(backoff)", "-q"] + hosts + [nil]
    var cargs = argv.map { $0.flatMap { UnsafeMutablePointer<Int8>(strdup($0)) } }

    let observer = NotificationCenter.default.addObserver(forName: NSNotification.Name(rawValue: "fpingxProgress"), object: nil, queue: OperationQueue()) { (notification) in
        if let p = notification.userInfo!["progress"] as? Float {
            progress?(p > 1 ? 1 : p)
        }
    }

    DispatchQueue.global(qos: .background).async {
        let resultsArrarPtr = fping(Int32(argv.count), &cargs, progressCCallback)!
        var hostPtr = resultsArrarPtr.pointee

        var results: [String: PngResult] = [:]
        while (hostPtr != nil) {
            let h = hostPtr!.pointee
            let host = String(cString: h.host)
            let result = PngResult(host: host, xmt: Int(h.num_sent), rcv: Int(h.num_recv), avg: h.num_recv > 0 ? Float(h.total_time / h.num_recv / 100) : nil, min: h.num_recv > 0 ? Int(h.min_reply / 100) : nil, max: h.num_recv > 0 ? Int(h.max_reply / 100) : nil, jitt: (h.jitter / Float(count)))
            results[host] = result
            let freeNode = hostPtr
            hostPtr = hostPtr?.pointee.ev_next
            free(UnsafeMutableRawPointer(freeNode))
        }

        free(UnsafeMutablePointer(resultsArrarPtr))
        completion(results)
        NotificationCenter.default.removeObserver(observer)
        for ptr in cargs { free(UnsafeMutablePointer(ptr)) }
    }

}`

[auerswal]

The error looks as if you created a too restrictive environment for fping to work.