dio.cxx File Reference

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/io.h>

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Functions
int	main (int argc, char **argv)

Function Documentation

main()

int main	(	int	argc,
		char **	argv
	)

Definition at line 23 of file dio.cxx.

{
   int status;
 
   /* Grant access to the device's ioports */
   status = iopl(3);
   if (status < 0) {
      perror("iopl()");
      exit(2);
   }
 
   /* Surrender root privileges - the exec()ed program will keep IO
      access to the IO ports (see "man 2 iopl") */
   if (setuid(getuid()) < 0) {
      perror("setuid()");
      exit(2);
   }
 
   /* Check command arguments */
   if (argc < 2) {
      fprintf(stderr, "Usage: %s program [arguments]\n", argv[0]);
      exit(1);
   }
 
   /* Execute the program (with any supplied command line args) */
   if (execvp(argv[1], &argv[1]) < 0) {
      perror(argv[1]);
      exit(2);
   }
   return 0;
}

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