/*************************************************************************\
*                  Copyright (C) Michael Kerrisk, 2026.                   *
*                                                                         *
* This program is free software. You may use, modify, and redistribute it *
* under the terms of the GNU General Public License as published by the   *
* Free Software Foundation, either version 3 or (at your option) any      *
* later version. This program is distributed without any warranty.  See   *
* the file COPYING.gpl-v3 for details.                                    *
\*************************************************************************/

#define _GNU_SOURCE
#include <time.h>
#include <utmpx.h>
#include <paths.h>
#include "tlpi_hdr.h"

int
main(int argc, char *argv[])
{
    struct utmpx *ut;

    if (argc > 1 && strcmp(argv[1], "--help") == 0)
        usageErr("%s [utmp-pathname]\n", argv[0]);

    if (argc > 1)               /* Use alternate file if supplied */
        if (utmpxname(argv[1]) == -1)
            errExit("utmpxname");

    setutxent();

    printf("user     type        PID line   id  host      date/time\n");

    while ((ut = getutxent()) != NULL) {        /* Sequential scan to EOF */
        printf("%-8s ", ut->ut_user);
        printf("%-9.9s ",
                (ut->ut_type == EMPTY) ?         "EMPTY" :
                (ut->ut_type == RUN_LVL) ?       "RUN_LVL" :
                (ut->ut_type == BOOT_TIME) ?     "BOOT_TIME" :
                (ut->ut_type == NEW_TIME) ?      "NEW_TIME" :
                (ut->ut_type == OLD_TIME) ?      "OLD_TIME" :
                (ut->ut_type == INIT_PROCESS) ?  "INIT_PR" :
                (ut->ut_type == LOGIN_PROCESS) ? "LOGIN_PR" :
                (ut->ut_type == USER_PROCESS) ?  "USER_PR" :
                (ut->ut_type == DEAD_PROCESS) ?  "DEAD_PR" : "???");
        printf("%5ld %-6.6s %-3.5s %-9.9s ", (long) ut->ut_pid,
                ut->ut_line, ut->ut_id, ut->ut_host);
        time_t tv_sec = ut->ut_tv.tv_sec;
        printf("%s", ctime(&tv_sec));
    }
    endutxent();
    exit(EXIT_SUCCESS);
}