execnofd - run a program after closing file descriptors >2

execnofd.c

/* execnofd 
 *
 * exec a program after closing all fd's > 2
 *
 * Syntax: execnofd <command> <options>
 *
 * Example: execnofd ls -l /home
 *
*/

#include <stdio.h>
#include <unistd.h>

int main(int argc, char *argv[]) {
  int maxfd = sysconf(_SC_OPEN_MAX);
  
  for(int i = 3; i < maxfd; i++) {
    close(i);
  }
  
  execvp(argv[0], &argv[1]);
}