multithreading

问题 I want to show the progress of Data being fetched from Database in a Progressbar . Currently i am updating the content of a Button . Have no idea how to implement in this code . private async void FetchInvoicesDataFunc(object sender, RoutedEventArgs e) { ProgressBtn.Content = "Loading Data ..."; InvoiceGrid.ItemsSource = await Task.Run(FetchInvoiceDataAsync); ProgressBtn.Content = "Loaded !"; } private async Task<List<Invoice>> FetchInvoiceDataAsync() { List<Invoice> result; using(var context

问题 Please help me to improve this code: import base64 import hashlib import threading import socket class WebSocketServer: def __init__(self, host, port, limit, **kwargs): """ Initialize websocket server. :param host: Host name as IP address or text definition. :param port: Port number, which server will listen. :param limit: Limit of connections in queue. :param kwargs: A dict of key/value pairs. It MAY contains:<br> <b>onconnect</b> - function, called after client connected. <b>handshake</b> -

问题 The two following single-threading and multi-threading scripts are taking the same time when I give as input a big number like 555550000 single thread import threading, time a=[] def print_factors(x): for i in range(1, x + 1): if x % i == 0: a.append(i) n=int(input("Please enter a large number")) print ("Starting time is %s" % ( time.ctime(time.time()) )) print("The factors of",n,"are:") thread = threading.Thread(target=print_factors,args=(n,)) thread.start() thread.join() print("Finishing

问题 According to documentation, WaitHandle in .NET should be explicitly/implicitly disposed. However, I'm having trouble achieving this for the following basic synchronization task: a time consuming task is being executed on a thread. the main thread waits for the task to complete for a predefined time-period. The main thread must proceed if a. the task is completed or b. the timeout occurred. Here my attempt at using an AutoResetEvent object: using(var waitHandle = new AutoResetEvent(false)){

问题 There are 101 things stored in THINGS variable. The code declares 101 threads and executes them all at once instantly all at the same time. I wonder if we can limit the number of the active threads to just 12. At first only 12 threads should pick their 12 THINGS to process. The rest of the threads should be waiting for the first 12 to finish their jobs. When the first 12 threads are all done then the next 12 threads would pick up the next 12 THINGS to process. And so one. Would it be possible

问题 I'm trying to implement a tool that starts 2 ssh connections and executes a script that requires root permission. Here is a very simple implementation: void* SshConnection(void* args) { char buffer[5000]; FILE* popenReturn = NULL; //get the hostname to connect to const char* hostname = (const char*)args; snprintf(buffer, sizeof(buffer), "/usr/bin/gnome-terminal -x bash -c \"" "ssh -t user@%s " "-i /home/user/.ssh/key.key " "\\\"/home/user/DoRootThings.bash\\\" ",hostname); popenReturn = popen

问题 Say I have a List of values that I accessed by different threads. So I make it thread safe by doing something like this: private static object syncObject; syncObject = new Object(); public List<double> MyList { get { lock(syncObject) { return myList;} } set { lock(syncObject) { myList = value;} } } If in one of my functions, I need to access the Count attribute of the List , it may not be thread safe anymore. So how do I write it such that even when accessing the attributes, it will be thread

问题 Say I have a List of values that I accessed by different threads. So I make it thread safe by doing something like this: private static object syncObject; syncObject = new Object(); public List<double> MyList { get { lock(syncObject) { return myList;} } set { lock(syncObject) { myList = value;} } } If in one of my functions, I need to access the Count attribute of the List , it may not be thread safe anymore. So how do I write it such that even when accessing the attributes, it will be thread

问题 Code snippet: void RunThread(void* unused_args) { PSECURITY_DESCRIPTOR sdsc; ULONG size; ConvertStringSecurityDescriptorToSecurityDescriptor("S:(ML;;NW;;;LW)", SDDL_REVISION_1, &sdsc, &size); SECURITY_ATTRIBUTES sa; sa.nLength = sizeof(sa); sa.bInheritHandle = false; sa.lpSecurityDescriptor = sdsc; HANDLE pipe = CreateNamedPipe("\\.\pipe\mmaivpc_test_pipe", PIPE_ACCESS_DUPLEX, PIPE_TYPE_BYTE, 255, 1024, 1024, 0, &sa); DWORD error = GetLastError(); } If you haven't figured it out from the

问题 I have this code doing what I want: TriggerSomeExternalProcess(); double secondsElapsed = 0; DateTime startTime = DateTime.UtcNow; double timeoutInSeconds = 10; while (secondsElapsed < timeoutInSeconds) { // TODO: this seems bad... secondsElapsed = DateTime.UtcNow.Subtract(startTime).TotalSeconds; } CheckStatusOfExternalProcess(); The goal is to TriggerSomeExternalProcess and then CheckStatusOfSomeExternalProcess - but that process runs on the same thread so I can't do Thread.Sleep() . It's