How do you spawn another process in C?

It really depends on what you’re trying to do, exactly, as it’s: OS dependent Not quite clear what you’re trying to do. Nevertheless, I’ll try to provide some information for you to decide. On UNIX, fork() creates a clone of your process from the place where you called fork. Meaning, if I have the following … Read more

How can I capture the stdout from a process that is ALREADY running

True solution for OSX Write the following function to your ~/.bashrc or ~/.zshrc. capture() { sudo dtrace -p “$1” -qn ‘ syscall::write*:entry /pid == $target && arg0 == 1/ { printf(“%s”, copyinstr(arg1, arg2)); } ‘ } Usage: example@localhost:~$ perl -e ‘STDOUT->autoflush; while (1) { print “Hello\n”; sleep 1; }’ >/dev/null & [1] 97755 example@localhost:~$ capture … Read more

Async process start and wait for it to finish

“and waiting must be async” – I’m not trying to be funny, but isn’t that a contradiction in terms? However, since you are starting a Process, the Exited event may help: ProcessStartInfo startInfo = null; Process process = Process.Start(startInfo); process.EnableRaisingEvents = true; process.Exited += delegate {/* clean up*/}; If you want to actually wait (timeout … Read more

CreateProcess error=2, The system cannot find the file specified

Assuming that winrar.exe is in the PATH, then Runtime.exec is capable of finding it, if it is not, you will need to supply the fully qualified path to it, for example, assuming winrar.exe is installed in C:/Program Files/WinRAR you would need to use something like… p=r.exec(“C:/Program Files/WinRAR/winrar x h:\\myjar.jar *.* h:\\new”); Personally, I would recommend … Read more

How to kill process inside container? Docker top command

When I reproduce your situation I see different PIDs between docker top <container> and docker exec -it <container> ps -aux. When you do docker exec the command is executed inside the container => should use container’s pid. Otherwise you could do the kill without docker straight from the host, in your case: sudo kill -9 … Read more

How is socket connection being handled in a forked process

First, accept() the incoming connection. The accepting process now has a handle to the listening socket, and the newly accepted socket. Fork and: In the child: Close the listening socket. Do stuff with the accepted socket. In the parent: Close the accepted socket. Resume the accept loop. The various socket resources will be reclaimed when … Read more

How do ‘cluster’ and ‘worker_threads’ work in Node.js?

Effectively what you are differing is process based vs thread based. Threads share memory (e.g. SharedArrayBuffer) whereas processes don’t. Essentially they are the same thing categorically. cluster One process is launched on each CPU and can communicate via IPC. Each process has it’s own memory with it’s own Node (v8) instance. Creating tons of them … Read more

Starting a process in Java?

http://www.rgagnon.com/javadetails/java-0014.html import java.io.BufferedReader; import java.io.InputStreamReader; import java.nio.file.Paths; public class CmdExec { public static void main(String args[]) { try { // enter code here Process p = Runtime.getRuntime().exec( Paths.get(System.getenv(“windir”), “system32”, “tree.com /A”).toString() ); // enter code here try(BufferedReader input = new BufferedReader(new InputStreamReader(p.getInputStream()))) { String line; while ((line = input.readLine()) != null) { System.out.println(line); } } … Read more

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)