UNIX/3b.c at master · bvpranu97/UNIX · GitHub

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#include <sys/types.h>
#include <sys/stat.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <errno.h>
#include <unistd.h>
#include <syslog.h>
#include <string.h>

int main(void) {

    FILE* fd;
        pid_t pid, sid;
        pid = fork();
        if (pid < 0)
                exit(EXIT_FAILURE);

        if (pid > 0)
                exit(EXIT_SUCCESS);

        umask(0);

        sid = setsid();
        if (sid < 0)
                exit(EXIT_FAILURE);

        if ((chdir("/")) < 0)
                exit(EXIT_FAILURE);

        close(STDIN_FILENO);
        close(STDOUT_FILENO);
        close(STDERR_FILENO);

        fd=fopen("/home/hello/myfile.txt","w+");
        while (1) {
           fprintf(fd,"Running");
           fflush(fd);
           sleep(5);
        }

   exit(EXIT_SUCCESS);
}