child-process

问题 I use nodejs to captured its child process's stdout data, but always captured the former part of child process's stdout data. When I add fllush(stdout) ，It works OK. But I don't know why, and don't want to add flush(stdout). Here is my code: var tail_child = spawn(exefile, [arg1, arg2, arg3]); tail_child.stdin.write('msg\n'); tail_child.stdout.on('data', function(data) { console.log(data); }); child_process.c printf("data\n"); Need your help! Thank you very much! 回答1: By default, stdout in

问题 I'm running a Python script through a child process in Node.js, like this: require('child_process').exec('python celulas.py', function (error, stdout, stderr) { child.stdout.pipe(process.stdout); }); but Node doesn't wait for it to finish. How can I wait for the process to finish? EDIT: Is it possible to do this by running the child process in a module I call from the main script? 回答1: You should use exec-sync That allow your script to wait that you exec is done really easy to use: var

问题 I have a program "Sample" which takes input both from stdin and a non-standard file descriptor (3 or 4) as shown below int pfds[2]; pipe(pfds); printf("%s","\nEnter input for stdin"); read(0, pO, 5); printf("\nEnter input for fds 3"); read(pfds[0], pX, 5); printf("\nOutput stout"); write(1, pO, strlen(pO)); printf("\nOutput fd 4"); write(pfds[1], pX, strlen(pX)); Now i have another program "Operator" which executes the above program(Sample) in a child process using execv. Now what i want is

问题 I am trying to spawn an external process phantomjs using node's child_process and then send information to that process after it was initialized, is that possible? I have the following code: var spawn = require('child_process').spawn, child = spawn('phantomjs'); child.stdin.setEncoding = 'utf-8'; child.stdout.pipe(process.stdout); child.stdin.write("console.log('Hello from PhantomJS')"); But the only thing I got on the stdout is the initial prompt for phantomjs console. phantomjs> So it seems

问题 I have two separate node applications. I'd like one of them to be able to start the other one at some point in the code. How would I go about doing this? 回答1: Use child_process.fork(). It is similar to spawn() , but is used to create entire new instances of V8. Therefore it is specially used for running new instances of Node. If you are just executing a command, then use spawn() or exec() . var fork = require('child_process').fork; var child = fork('./script'); Note that when using fork() ,

问题 I have two separate node applications. I'd like one of them to be able to start the other one at some point in the code. How would I go about doing this? 回答1: Use child_process.fork(). It is similar to spawn() , but is used to create entire new instances of V8. Therefore it is specially used for running new instances of Node. If you are just executing a command, then use spawn() or exec() . var fork = require('child_process').fork; var child = fork('./script'); Note that when using fork() ,

问题 I am using spawn to spawn a long running process that sends output over time to stdio, and is read and processed by my nodejs script. The tricky part is that I cannot guarantee that the command sent will always be valid. How can I catch an error in spawning? Preferably this will not involve installing a global exception handler, since I don't want to handle any other exceptions. (If that's the only way, I would need to figure out when the spawned process has started up correctly and then

问题 can someone help me about how to create multiple child processes which have the same parent in order to do "some" part of particular job? for example, an external sorting algorithm which is applied with child processes; each child process sorts a part of data and finally the parent merges them.. EDIT: Maybe I should mention the forking multiple child processes with loop.. 回答1: Here is how to fork 10 children and wait for them to finish: pid_t pids[10]; int i; int n = 10; /* Start children. */

问题 I have a .NET class library that spins up a secondary process which is kept running until I dispose of the object. Due to some occurances of the program lingering in memory, I've decided to add an integration test to ensure that if I let the object lapse to GC/Finalization, that process is spun down. However, since the process is the Mercurial command line client, and my build server is already running Mercurial as part of its own operations, I envision situations where Mercurial is either

问题 This question already has answers here : How to create threads in nodejs (11 answers) Closed 4 years ago . So out of curiosity, I was thinking of creating my own thread pool in nodejs from which I can run number of threads in parallelly? Been looking to webworker-threads and npool but not being to understand much from it.. Is it possible to create a thread pool in nodejs? Also how to execute number of threads from the pool created in parallel number of threads/chid_processes? Like is