background-process

问题 I have a script (lets call it parent.sh) that makes 2 calls to a second script (child.sh) that runs a java process. The child.sh scripts are run in the background by placing an & at the end of the line in parent.sh. However, when i run parent.sh, i need to press Ctrl+C to return to the terminal screen. What is the reason for this? Is it something to do with the fact that the child.sh processes are running under the parent.sh process. So the parent.sh doesn't die until the childs do? parent.sh

问题 Good evening, I've been trying to achieve something for several days now and I literally don't know what else to try, I've basically tried everything I found online and it still doesn't work but I have the feeling that once I find the solution it must be something quite simple. I'm working on a bigger project, but here I'm just trying to get a very simple example to work which I can later adapt to my project. What I want to do I want to have a counter add +1 every second for 1200 seconds (20

问题 Good evening, I've been trying to achieve something for several days now and I literally don't know what else to try, I've basically tried everything I found online and it still doesn't work but I have the feeling that once I find the solution it must be something quite simple. I'm working on a bigger project, but here I'm just trying to get a very simple example to work which I can later adapt to my project. What I want to do I want to have a counter add +1 every second for 1200 seconds (20

问题 I'm trying to understand the deferredLocations feature. As per apple docs, the following should work, and it does when I run it on the simulator, but once I install the app on my iPhone 6s and disconnect the iPhone and run the app, the locations updates do not get deferred. I'm using XCode 8 and swift 3. Here is the code: override func viewDidLoad() { super.viewDidLoad() // Do any additional setup after loading the view, typically from a nib. locationManager=CLLocationManager()

问题 I'm working on an app that needs to run through a protocol from beginning to end. How do I force the app to always start at the beginning when brought back from the background, regardless of where it was left. Thanks 回答1: If your goal is to restart the app from scratch at every start up, simply add/change the key UIApplicationExitsOnSuspend to YES in your info.plist file Here's the relevant link in the documentation http://developer.apple.com/library/ios/#documentation/general/Reference

问题 I have a very simple controller: def create @poem = Poem.new(params[:poem]) @poem.prose = @poem.content @poem.save Resque.enqueue(PoemWork, @poem.id) .... and a very simple worker: class PoemWork @queue = :poem_queue def self.perform(poem_id) @poem = Poem.find(poem_id) txt = @poem.content #do stuff here @poem.save end end And I keep getting "Couldn't find Poem with id=53" or smth. like that... I tried passing just string, just integer etc.. but it also ends with ActiveRecord::RecordNotFound

问题 I get the general idea of how this common version :(){ :|:& };: of the bash fork bomb works. However, I've seen another version (for bash in particular) #!/bin/bash $0 & $0 & on the Wikipedia fork bomb article and in an SO answer to a closed duplicate of the original fork bomb question I mentioned above. I'm looking for an explanation of how the second (perhaps less common) version of the fork bomb works. I've commented the code below with my current understanding of what it does, but I don't

问题 I get the general idea of how this common version :(){ :|:& };: of the bash fork bomb works. However, I've seen another version (for bash in particular) #!/bin/bash $0 & $0 & on the Wikipedia fork bomb article and in an SO answer to a closed duplicate of the original fork bomb question I mentioned above. I'm looking for an explanation of how the second (perhaps less common) version of the fork bomb works. I've commented the code below with my current understanding of what it does, but I don't

问题 I want to write a program that can be run as a backgrounded task (i.e. my-thing & ), and that will beautifully provide relevant output when necessary. However, with background tasks that print to the terminal, there's always this annoying little progression: bash-3.2$ my-thing & ▏ bash-3.2$ my-thing & bash-3.2$ -- Hello from my-thing! -- now let me start doing what I do best ... ▏ … notice that we now have no prompt before the cursor, not to mention that there's an ugly erraneous prompt where

问题 I am developing an iOS app which receives apple's remote push notifications at a particular time interval. The notifications are received successfully when app is active as well as when app is in background. But when app is terminated from app switcher/dock, notifications are not received until the app is started again. I have tried following code to keep app alive in background. This same code is implemented in applicationWillTerminate: method, but it did not work. __block