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

int main(void) {
  struct utmpx ut;
  struct utmpx * utp;
  const char * user = "foobar";
  const char * line = "offline";

  memset(&ut, 0, sizeof(ut));
  memcpy(&ut.ut_user[0], user, strlen(user));
  memcpy(&ut.ut_id[0], "1234", 4);
  memcpy(&ut.ut_line[0], line, strlen(line));
  ut.ut_pid = getpid();
  ut.ut_type = USER_PROCESS;

  setutxent();
  /* Create entry */
  if (pututxline(&ut) == NULL) {
    puts("putuxtline failed. are you superuser?");
    return 1;
  }

  setutxent();
  utp = getutxent();
  while ((utp != NULL) && (utp->ut_pid != ut.ut_pid))
    utp = getutxent();
  if (utp == NULL) {
    puts("entry not found");
    return 1;
  }
  utp->ut_type = DEAD_PROCESS;
  /* Should overwrite existing? */
  pututxline(utp);

  setutxent();
  utp = getutxid(&ut);
  if (utp == NULL) {
    puts("entry not found");
    return 1;
  }
  utp->ut_type = DEAD_PROCESS;
  /* Should overwrite existing? */
  pututxline(utp);

  setutxent();
  utp = getutxline(&ut);
  if (utp == NULL) {
    puts("entry not found");
    return 1;
  }
  utp->ut_type = DEAD_PROCESS;
  /* Should overwrite existing? */
  pututxline(utp);

  return 0;
}