io

问题 I am running a big job, in cluster mode. However, I am only interested in two floats numbers, which I want to read somehow, when the job succeeds. Here what I am trying: from pyspark.context import SparkContext if __name__ == "__main__": sc = SparkContext(appName='foo') f = open('foo.txt', 'w') pi = 3.14 not_pi = 2.79 f.write(str(pi) + "\n") f.write(str(not_pi) + "\n") f.close() sc.stop() However, 'foo.txt' doesn't appear to be written anywhere (probably it gets written in an executor, or

问题 I am trying to iterate over files in a local directory: foreach (string name in Directory.GetFileSystemEntries(path)) { FileAttrtibutes att = File.GetAttributes(name) } One of the files in the folder at path is named "This is a test". GetAttributes() throws an exception on filenames with spaces. Apart from replacing spaces with some other character, how should I handle spaces in filenames in this circumstance? I apologise. I was a bit hasty. Let me redefine the problem, even though I now have

问题 I'm getting small dialog boxes that pop up saying I/O Error occurred . What causes this, and how should I fix this? Edit: what happens is that after i run my flash game, FlashDevelop will try to connect to the Flash debugger, but apparently fail and give me the above error. I have both the debug standalone player and the ActiveX debug control for Firefox. 回答1: To activate interactive debugging with haxe/Flash/FlashDevelop you have to add the fdb switch and network-sandbox. To do that open

问题 In C, I often want to handle data read from a file and data read from an array of strings the same way. Usually reading from a file is for production and from strings is for testing. I wind up writing a lot of code like this: void handle_line(char *line, Things *things) { ... } Things *read_from_chars(char *lines[]) { Things *things = Things_new(); for (int i = 0; lines[i] != NULL; i++) { handle_line(lines[i], things); } return things; } Things *read_from_input(FILE *input) { char *line =

问题 Three days i was trying to figure out how to read file using relative file path. In eclipse this compiles and works great, but when i export app. It says that it can't find the file. here is the screenshot and code i work on. This code works, but only in eclipse, it compiles and does job perfectly. But when i export it as as runnable jar file i get an error, that it cannot locate licenca.txt BufferedReader in = new BufferedReader(new FileReader(new File("licenca.txt").getPath())); String str;

问题 I'm working with an ASCII input/output stream over a Socket and speed is critical. I've heard using the right Java technique really makes a difference. I have a textbook that says using Buffers is the best way, but also suggests chaining with DataInputStreamReader. For output I'm using a BufferedOutputStream with OutputStreamWriter which seems to be fine. But I am unsure on what to use for the input stream. I'm working on new lines, so would Scanner be of any use? Speed is critical, I need to

问题 This is similar to Filter out broken pipe errors , but with complications - when a user presses the "stop" button on their browser while a template is executing (html/template.Execute or text/template.Execute), a broken pipe error occurs. However, I believe that the error returned by the text/template package is simply of type *errors.errorString as the broken pipe message appears to be wrapped in some other informational text and so no type assertion can be made to net.OpErr for comparison

问题 I need to redirect output of a spawned child process. This is what I tried but it doesn't work: Command::new(cmd) .args(&["--testnet", "--fast", format!("&>> {}", log_path).as_str()]) .stdin(Stdio::piped()) .stdout(Stdio::inherit()) .spawn() 回答1: To directly use a file as output without intermediate copying from a pipe, you have to pass the file descriptor. The code is platform-specific, but with conditional compilation you can make it work on Windows too. let f = File::create("foo.log")

问题 I have a JSON String generated in Java, and I need to send this String to another computer, which will be receiving it through JavaScript (because electron). The JavaScript computer could be far away, and will contact the Java app through the internet. The Java app is not a web app of sorts, it is a simple back end app. How would I do this? 回答1: To make your Java application reachable from outside, you need to somehow expose it to the network. There quite a few ways to do this, but arguably

问题 Trying to understand async-await in C#, and a bit stuck in a "chicken and egg" problem, maybe. Does an async method need to call another async for it to be asynchronous? As a high level example, I'm trying to do a simple write to the file system, but not sure how I can make this task awaitable, if at all. public Task<FileActionStatus> SaveAsync(path, data) { // Do some stuff, then... File.WriteAllBytes(path, data); // <-- Allow this to yield control? // ... then return result } That line of