Question

I am using Fedora linux where ulimit -n 10000 increases file limit upto 10000. I want to achieve the same using java program

How to write java program to increase file limit using ulimit
I have tried with the below program but it didnot work well. The program didnot give any error. but didnot increase file limit also

public class IncreaseFIle {
    public static void main(String[] args) {

       String command = "/bin/bash ulimit -n 10000";
//        String command = "pwd";
        try {
            Runtime.getRuntime().exec(command);

        } catch (IOException ex) {
            ex.printStackTrace();
        }
    }
}

Thanks
Sunil Kumar Sahoo

Answer 1

From the man page:

The ulimit utility shall set or report the file-size writing limit imposed on files written by the shell and its child processes.

You java program is not the shell or one of its child process – it is the ancestor process, and therefore is unaffected by anything that its child process does. To get another ulimit you must somehow contrive to call ulimit before java is started.