/*
 * sar: report system activity
 * (C) 1999-2019 by Sebastien GODARD (sysstat <at> orange.fr)
 *
 ***************************************************************************
 * This program is free software; you can redistribute it and/or modify it *
 * under the terms of the GNU General Public License as published  by  the *
 * Free Software Foundation; either version 2 of the License, or (at  your *
 * option) any later version.                                              *
 *                                                                         *
 * This program is distributed in the hope that it  will  be  useful,  but *
 * WITHOUT ANY WARRANTY; without the implied warranty  of  MERCHANTABILITY *
 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License *
 * for more details.                                                       *
 *                                                                         *
 * You should have received a copy of the GNU General Public License along *
 * with this program; if not, write to the Free Software Foundation, Inc., *
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335 USA              *
 ***************************************************************************
 */

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <time.h>
#include <errno.h>
#include <signal.h>
#include <sys/stat.h>

#include "version.h"
#include "sa.h"

#ifdef USE_NLS
#include <locale.h>
#include <libintl.h>
#define _(string) gettext(string)
#else
#define _(string) (string)
#endif

#ifdef USE_SCCSID
#define SCCSID "@(#)sysstat-" VERSION ": " __FILE__ " compiled " __DATE__ " " __TIME__
char *sccsid(void) { return (SCCSID); }
#endif

/* Interval and count parameters */
long interval = -1, count = 0;

/* TRUE if a header line must be printed */
int dis = TRUE;
/* TRUE if data read from file don't match current machine's endianness */
int endian_mismatch = FALSE;
/* TRUE if file's data come from a 64 bit machine */
int arch_64 = FALSE;
/* Number of decimal places */
int dplaces_nr = -1;

unsigned int flags = 0;
unsigned int dm_major;	/* Device-mapper major number */

char timestamp[2][TIMESTAMP_LEN];
extern unsigned int rec_types_nr[];

unsigned long avg_count = 0;

/* File header */
struct file_header file_hdr;

/* Current record header */
struct record_header record_hdr[3];

/*
 * Activity sequence.
 * This array must always be entirely filled (even with trailing zeros).
 */
unsigned int id_seq[NR_ACT];

struct tm rectime;

/* Contain the date specified by -s and -e options */
struct tstamp tm_start, tm_end;

char *args[MAX_ARGV_NR];

extern struct activity *act[];
extern struct report_format sar_fmt;

struct sigaction int_act;
int sigint_caught = 0;

/*
 ***************************************************************************
 * Print usage title message.
 *
 * IN:
 * @progname	Name of sysstat command
 ***************************************************************************
 */
void print_usage_title(FILE *fp, char *progname)
{
	fprintf(fp, _("Usage: %s [ options ] [ <interval> [ <count> ] ]\n"),
		progname);
}

/*
 ***************************************************************************
 * Print usage and exit.
 *
 * IN:
 * @progname	Name of sysstat command
 ***************************************************************************
 */
void usage(char *progname)
{
	print_usage_title(stderr, progname);
	fprintf(stderr, _("Options are:\n"
			  "[ -A ] [ -B ] [ -b ] [ -C ] [ -D ] [ -d ] [ -F [ MOUNT ] ] [ -H ] [ -h ]\n"
			  "[ -p ] [ -q ] [ -r [ ALL ] ] [ -S ] [ -t ] [ -u [ ALL ] ] [ -V ]\n"
			  "[ -v ] [ -W ] [ -w ] [ -y ] [ -z ]\n"
			  "[ -I { <int_list> | SUM | ALL } ] [ -P { <cpu_list> | ALL } ]\n"
			  "[ -m { <keyword> [,...] | ALL } ] [ -n { <keyword> [,...] | ALL } ]\n"
			  "[ --dev=<dev_list> ] [ --fs=<fs_list> ] [ --iface=<iface_list> ]\n"
			  "[ --dec={ 0 | 1 | 2 } ] [ --help ] [ --human ] [ --sadc ]\n"
			  "[ -j { ID | LABEL | PATH | UUID | ... } ]\n"
			  "[ -f [ <filename> ] | -o [ <filename> ] | -[0-9]+ ]\n"
			  "[ -i <interval> ] [ -s [ <hh:mm[:ss]> ] ] [ -e [ <hh:mm[:ss]> ] ]\n"));
	exit(1);
}

/*
 ***************************************************************************
 * Display a short help message and exit.
 *
 * IN:
 * @progname	Name of sysstat command
 ***************************************************************************
 */
void display_help(char *progname)
{
	print_usage_title(stdout, progname);
	printf(_("Main options and reports (report name between square brackets):\n"));
	printf(_("\t-B\tPaging statistics [A_PAGE]\n"));
	printf(_("\t-b\tI/O and transfer rate statistics [A_IO]\n"));
	printf(_("\t-d\tBlock devices statistics [A_DISK]\n"));
	printf(_("\t-F [ MOUNT ]\n"));
	printf(_("\t\tFilesystems statistics [A_FS]\n"));
	printf(_("\t-H\tHugepages utilization statistics [A_HUGE]\n"));
	printf(_("\t-I { <int_list> | SUM | ALL }\n"
		 "\t\tInterrupts statistics [A_IRQ]\n"));
	printf(_("\t-m { <keyword> [,...] | ALL }\n"
		 "\t\tPower management statistics [A_PWR_...]\n"
		 "\t\tKeywords are:\n"
		 "\t\tCPU\tCPU instantaneous clock frequency\n"
		 "\t\tFAN\tFans speed\n"
		 "\t\tFREQ\tCPU average clock frequency\n"
		 "\t\tIN\tVoltage inputs\n"
		 "\t\tTEMP\tDevices temperature\n"
		 "\t\tUSB\tUSB devices plugged into the system\n"));
	printf(_("\t-n { <keyword> [,...] | ALL }\n"
		 "\t\tNetwork statistics [A_NET_...]\n"
		 "\t\tKeywords are:\n"
		 "\t\tDEV\tNetwork interfaces\n"
		 "\t\tEDEV\tNetwork interfaces (errors)\n"
		 "\t\tNFS\tNFS client\n"
		 "\t\tNFSD\tNFS server\n"
		 "\t\tSOCK\tSockets\t(v4)\n"
		 "\t\tIP\tIP traffic\t(v4)\n"
		 "\t\tEIP\tIP traffic\t(v4) (errors)\n"
		 "\t\tICMP\tICMP traffic\t(v4)\n"
		 "\t\tEICMP\tICMP traffic\t(v4) (errors)\n"
		 "\t\tTCP\tTCP traffic\t(v4)\n"
		 "\t\tETCP\tTCP traffic\t(v4) (errors)\n"
		 "\t\tUDP\tUDP traffic\t(v4)\n"
		 "\t\tSOCK6\tSockets\t(v6)\n"
		 "\t\tIP6\tIP traffic\t(v6)\n"
		 "\t\tEIP6\tIP traffic\t(v6) (errors)\n"
		 "\t\tICMP6\tICMP traffic\t(v6)\n"
		 "\t\tEICMP6\tICMP traffic\t(v6) (errors)\n"
		 "\t\tUDP6\tUDP traffic\t(v6)\n"
		 "\t\tFC\tFibre channel HBAs\n"
		 "\t\tSOFT\tSoftware-based network processing\n"));
	printf(_("\t-q\tQueue length and load average statistics [A_QUEUE]\n"));
	printf(_("\t-r [ ALL ]\n"
		 "\t\tMemory utilization statistics [A_MEMORY]\n"));
	printf(_("\t-S\tSwap space utilization statistics [A_MEMORY]\n"));
	printf(_("\t-u [ ALL ]\n"
		 "\t\tCPU utilization statistics [A_CPU]\n"));
	printf(_("\t-v\tKernel tables statistics [A_KTABLES]\n"));
	printf(_("\t-W\tSwapping statistics [A_SWAP]\n"));
	printf(_("\t-w\tTask creation and system switching statistics [A_PCSW]\n"));
	printf(_("\t-y\tTTY devices statistics [A_SERIAL]\n"));
	exit(0);
}

/*
 ***************************************************************************
 * Give a hint to the user about where is located the data collector.
 ***************************************************************************
 */
void which_sadc(void)
{
	struct stat buf;

	if (stat(SADC_PATH, &buf) < 0) {
		printf(_("Data collector will be sought in PATH\n"));
	}
	else {
		printf(_("Data collector found: %s\n"), SADC_PATH);
	}
	exit(0);
}

/*
 ***************************************************************************
 * SIGINT signal handler.
 *
 * IN:
 * @sig	Signal number.
 ***************************************************************************
 */
void int_handler(int sig)
{
	sigint_caught = 1;
	printf("\n");	/* Skip "^C" displayed on screen */

}

/*
 ***************************************************************************
 * Init some structures.
 ***************************************************************************
 */
void init_structures(void)
{
	int i;

	for (i = 0; i < 3; i++)
		memset(&record_hdr[i], 0, RECORD_HEADER_SIZE);
}

/*
 ***************************************************************************
 * Allocate memory for sadc args.
 *
 * IN:
 * @i		Argument number.
 * @ltemp	Argument value.
 ***************************************************************************
 */
void salloc(int i, char *ltemp)
{
	if ((args[i] = (char *) malloc(strlen(ltemp) + 1)) == NULL) {
		perror("malloc");
		exit(4);
	}
	strcpy(args[i], ltemp);
}

/*
 ***************************************************************************
 * Display an error message.
 *
 * IN:
 * @error_code	Code of error message to display.
 ***************************************************************************
 */
void print_read_error(int error_code)
{
	switch (error_code) {

		case END_OF_DATA_UNEXPECTED:
			/* Happens when the data collector doesn't send enough data */
			fprintf(stderr, _("End of data collecting unexpected\n"));
			break;

		default:
			/* Strange data sent by sadc...! */
			fprintf(stderr, _("Inconsistent input data\n"));
			break;
	}
	exit(3);
}

/*
 ***************************************************************************
 * Check that every selected activity actually belongs to the sequence list.
 * If not, then the activity should be unselected since it will not be sent
 * by sadc. An activity can be not sent if its number of items is zero.
 *
 * IN:
 * @act_nr	Size of sequence list.
 ***************************************************************************
 */
void reverse_check_act(unsigned int act_nr)
{
	int i, j;

	for (i = 0; i < NR_ACT; i++) {

		if (IS_SELECTED(act[i]->options)) {

			for (j = 0; j < act_nr; j++) {
				if (id_seq[j] == act[i]->id)
					break;
			}
			if (j == act_nr)
				act[i]->options &= ~AO_SELECTED;
		}
	}
}

/*
 ***************************************************************************
 * Determine if a stat header line has to be displayed.
 *
 * RETURNS:
 * TRUE if a header line has to be displayed.
 ***************************************************************************
*/
int check_line_hdr(void)
{
	int i, rc = FALSE;

	/* Get number of options entered on the command line */
	if (get_activity_nr(act, AO_SELECTED, COUNT_OUTPUTS) > 1)
		return TRUE;

	for (i = 0; i < NR_ACT; i++) {
		if (IS_SELECTED(act[i]->options)) {
			/* Special processing for activities using a bitmap */
			if (act[i]->bitmap) {
				if (count_bits(act[i]->bitmap->b_array,
					       BITMAP_SIZE(act[i]->bitmap->b_size)) > 1) {
					rc = TRUE;
				}
			}
			else if (act[i]->nr_ini > 1) {
				rc = TRUE;
			}
			/* Stop now since we have only one selected activity */
			break;
		}
	}

	return rc;
}

/*
 ***************************************************************************
 * Print statistics average.
 *
 * IN:
 * @curr		Index in array for current sample statistics.
 * @read_from_file	Set to TRUE if stats are read from a system activity
 * 			data file.
 * @act_id		Activity that can be displayed, or ~0 for all.
 *			Remember that when reading stats from a file, only
 *			one activity can be displayed at a time.
 ***************************************************************************
 */
void write_stats_avg(int curr, int read_from_file, unsigned int act_id)
{
	int i;
	unsigned long long itv;

	/* Interval value in 1/100th of a second */
	itv = get_interval(record_hdr[2].uptime_cs, record_hdr[curr].uptime_cs);

	strncpy(timestamp[curr], _("Average:"), TIMESTAMP_LEN);
	timestamp[curr][TIMESTAMP_LEN - 1] = '\0';
	memcpy(timestamp[!curr], timestamp[curr], TIMESTAMP_LEN);

	/* Test stdout */
	TEST_STDOUT(STDOUT_FILENO);

	for (i = 0; i < NR_ACT; i++) {

		if ((act_id != ALL_ACTIVITIES) && (act[i]->id != act_id))
			continue;

		if (IS_SELECTED(act[i]->options) && (act[i]->nr[curr] > 0)) {
			/* Display current average activity statistics */
			(*act[i]->f_print_avg)(act[i], 2, curr, itv);
		}
	}

	if (read_from_file) {
		/*
		 * Reset number of lines printed only if we read stats
		 * from a system activity file.
		 */
		avg_count = 0;
	}
}

/*
 ***************************************************************************
 * Print system statistics.
 * This is called when we read stats either from a file or from sadc.
 *
 * IN:
 * @curr		Index in array for current sample statistics.
 * @read_from_file	Set to TRUE if stats are read from a system activity
 * 			data file.
 * @use_tm_start	Set to TRUE if option -s has been used.
 * @use_tm_end		Set to TRUE if option -e has been used.
 * @reset		Set to TRUE if last_uptime variable should be
 * 			reinitialized (used in next_slice() function).
 * @act_id		Activity that can be displayed or ~0 for all.
 *			Remember that when reading stats from a file, only
 *			one activity can be displayed at a time.
 * @reset_cd		TRUE if static cross_day variable should be reset
 * 			(see below).
 *
 * OUT:
 * @cnt			Number of remaining lines to display.
 *
 * RETURNS:
 * 1 if stats have been successfully displayed, and 0 otherwise.
 ***************************************************************************
 */
int write_stats(int curr, int read_from_file, long *cnt, int use_tm_start,
		int use_tm_end, int reset, unsigned int act_id, int reset_cd)
{
	int i;
	unsigned long long itv;
	static int cross_day = 0;

	if (reset_cd) {
		/*
		 * cross_day is a static variable that is set to 1 when the first
		 * record of stats from a new day is read from a unique data file
		 * (in the case where the file contains data from two consecutive
		 * days). When set to 1, every following records timestamp will
		 * have its hour value increased by 24.
		 * Yet when a new activity (being read from the file) is going to
		 * be displayed, we start reading the file from the beginning
		 * again, and so cross_day should be reset in this case.
		 */
		cross_day = 0;
	}

	/* Check time (1) */
	if (read_from_file) {
		if (!next_slice(record_hdr[2].uptime_cs, record_hdr[curr].uptime_cs,
				reset, interval))
			/* Not close enough to desired interval */
			return 0;
	}

	/* Get then set previous timestamp */
	if (sa_get_record_timestamp_struct(flags + S_F_LOCAL_TIME, &record_hdr[!curr],
					   &rectime, NULL))
		return 0;
	set_record_timestamp_string(flags, &record_hdr[!curr],
				    NULL, timestamp[!curr], TIMESTAMP_LEN, &rectime);

	/* Get then set current timestamp */
	if (sa_get_record_timestamp_struct(flags + S_F_LOCAL_TIME, &record_hdr[curr],
					   &rectime, NULL))
		return 0;
	set_record_timestamp_string(flags, &record_hdr[curr],
				    NULL, timestamp[curr], TIMESTAMP_LEN, &rectime);

	/* Check if we are beginning a new day */
	if (use_tm_start && record_hdr[!curr].ust_time &&
	    (record_hdr[curr].ust_time > record_hdr[!curr].ust_time) &&
	    (record_hdr[curr].hour < record_hdr[!curr].hour)) {
		cross_day = 1;
	}

	if (cross_day) {
		/*
		 * This is necessary if we want to properly handle something like:
		 * sar -s time_start -e time_end with
		 * time_start(day D) > time_end(day D+1)
		 */
		rectime.tm_hour += 24;
	}

	/* Check time (2) */
	if (use_tm_start && (datecmp(&rectime, &tm_start) < 0))
		/* it's too soon... */
		return 0;

	/* Get interval value in 1/100th of a second */
	get_itv_value(&record_hdr[curr], &record_hdr[!curr], &itv);

	/* Check time (3) */
	if (use_tm_end && (datecmp(&rectime, &tm_end) > 0)) {
		/* It's too late... */
		*cnt = 0;
		return 0;
	}

	avg_count++;

	/* Test stdout */
	TEST_STDOUT(STDOUT_FILENO);

	for (i = 0; i < NR_ACT; i++) {

		if ((act_id != ALL_ACTIVITIES) && (act[i]->id != act_id))
			continue;

		if (IS_SELECTED(act[i]->options) && (act[i]->nr[curr] > 0)) {
			/* Display current activity statistics */
			(*act[i]->f_print)(act[i], !curr, curr, itv);
		}
	}

	return 1;
}

/*
 ***************************************************************************
 * Display stats since system startup.
 *
 * IN:
 * @curr	Index in array for current sample statistics.
 ***************************************************************************
 */
void write_stats_startup(int curr)
{
	int i;

	/* Set to 0 previous structures corresponding to boot time */
	memset(&record_hdr[!curr], 0, RECORD_HEADER_SIZE);
	record_hdr[!curr].record_type = R_STATS;
	record_hdr[!curr].hour        = record_hdr[curr].hour;
	record_hdr[!curr].minute      = record_hdr[curr].minute;
	record_hdr[!curr].second      = record_hdr[curr].second;
	record_hdr[!curr].ust_time    = record_hdr[curr].ust_time;

	for (i = 0; i < NR_ACT; i++) {
		if (IS_SELECTED(act[i]->options) && (act[i]->nr[curr] > 0)) {
			/*
			 * Using nr[curr] and not nr[!curr] below because we initialize
			 * reference structures for each structure that has been
			 * currently read in memory.
			 * No problem with buffers allocation since they all have the
			 * same size.
			 */
			memset(act[i]->buf[!curr], 0,
			       (size_t) act[i]->msize * (size_t) act[i]->nr[curr] * (size_t) act[i]->nr2);
		}
	}

	flags |= S_F_SINCE_BOOT;
	dis = TRUE;

	write_stats(curr, USE_SADC, &count, NO_TM_START, NO_TM_END, NO_RESET,
		    ALL_ACTIVITIES, TRUE);

	exit(0);
}

/*
 ***************************************************************************
 * Read data sent by the data collector.
 *
 * IN:
 * @size	Number of bytes of data to read.
 *
 * OUT:
 * @buffer	Buffer where data will be saved.
 *
 * RETURNS:
 * 1 if end of file has been reached, 0 otherwise.
 ***************************************************************************
 */
int sa_read(void *buffer, size_t size)
{
	ssize_t n;

	while (size) {

		if ((n = read(STDIN_FILENO, buffer, size)) < 0) {
			perror("read");
			exit(2);
		}

		if (!n)
			return 1;	/* EOF */

		size -= n;
		buffer = (char *) buffer + n;
	}

	return 0;
}

/*
 ***************************************************************************
 * Display a restart message (contents of a R_RESTART record).
 *
 * IN:
 * @tab		Number of tabulations (unused here).
 * @action	Action expected from current function (unused here).
 * @cur_date	Date string of current restart message (unused here).
 * @cur_time	Time string of current restart message.
 * @utc		True if @cur_time is expressed in UTC (unused here).
 * @file_hdr	System activity file standard header.
 ***************************************************************************
 */
__printf_funct_t print_sar_restart(int *tab, int action, char *cur_date, char *cur_time,
				  int utc, struct file_header *file_hdr)
{
	char restart[64];

	printf("\n%-11s", cur_time);
	sprintf(restart, "  LINUX RESTART\t(%d CPU)\n",
		file_hdr->sa_cpu_nr > 1 ? file_hdr->sa_cpu_nr - 1 : 1);
	cprintf_s(IS_RESTART, "%s", restart);

}

/*
 ***************************************************************************
 * Display a comment (contents of R_COMMENT record).
 *
 * IN:
 * @tab		Number of tabulations (unused here).
 * @action	Action expected from current function (unused here).
 * @cur_date	Date string of current comment (unused here).
 * @cur_time	Time string of current comment.
 * @utc		True if @cur_time is expressed in UTC (unused here).
 * @comment	Comment to display.
 * @file_hdr	System activity file standard header (unused here).
 ***************************************************************************
 */
__print_funct_t print_sar_comment(int *tab, int action, char *cur_date, char *cur_time, int utc,
				  char *comment, struct file_header *file_hdr)
{
	printf("%-11s", cur_time);
	cprintf_s(IS_COMMENT, "  COM %s\n", comment);
}

/*
 ***************************************************************************
 * Read the various statistics sent by the data collector (sadc).
 *
 * IN:
 * @curr	Index in array for current sample statistics.
 ***************************************************************************
 */
void read_sadc_stat_bunch(int curr)
{
	int i, p;

	/* Read record header (type is always R_STATS since it is read from sadc) */
	if (sa_read(&record_hdr[curr], RECORD_HEADER_SIZE)) {
		/*
		 * SIGINT (sent by sadc) is likely to be received
		 * while we are stuck in sa_read().
		 * If this happens then no data have to be read.
		 */
		if (sigint_caught)
			return;

#ifdef DEBUG
		fprintf(stderr, "%s: Record header\n", __FUNCTION__);
#endif
		print_read_error(END_OF_DATA_UNEXPECTED);
	}

	for (i = 0; i < NR_ACT; i++) {

		if (!id_seq[i])
			continue;
		p = get_activity_position(act, id_seq[i], EXIT_IF_NOT_FOUND);

		if (HAS_COUNT_FUNCTION(act[p]->options)) {
			if (sa_read(&(act[p]->nr[curr]), sizeof(__nr_t))) {
#ifdef DEBUG
				fprintf(stderr, "%s: Nb of items\n", __FUNCTION__);
#endif
				print_read_error(END_OF_DATA_UNEXPECTED);
			}
			if ((act[p]->nr[curr] > act[p]->nr_max) || (act[p]->nr[curr] < 0)) {
#ifdef DEBUG
				fprintf(stderr, "%s: %s: nr=%d nr_max=%d\n",
					__FUNCTION__, act[p]->name, act[p]->nr[curr], act[p]->nr_max);
#endif
				print_read_error(INCONSISTENT_INPUT_DATA);
			}
			if (act[p]->nr[curr] > act[p]->nr_allocated) {
				reallocate_all_buffers(act[p], act[p]->nr[curr]);
			}


			/*
			 * For persistent activities, we must make sure that no statistics
                         * from a previous iteration remain, especially if the number
                         * of structures read is smaller than @nr_ini.
                         */
                        if (HAS_PERSISTENT_VALUES(act[p]->options)) {
                            memset(act[p]->buf[curr], 0,
                                   (size_t) act[p]->fsize * (size_t) act[p]->nr_ini * (size_t) act[p]->nr2);
                        }
                }
		if (sa_read(act[p]->buf[curr],
			    (size_t) act[p]->fsize * (size_t) act[p]->nr[curr] * (size_t) act[p]->nr2)) {
#ifdef DEBUG
			fprintf(stderr, "%s: Statistics\n", __FUNCTION__);
#endif
			print_read_error(END_OF_DATA_UNEXPECTED);
		}
	}
}

/*
 ***************************************************************************
 * Read stats for current activity from file and display them.
 *
 * IN:
 * @ifd		Input file descriptor.
 * @fpos	Position in file where reading must start.
 * @curr	Index in array for current sample statistics.
 * @rows	Number of rows of screen.
 * @act_id	Activity to display.
 * @file_actlst	List of activities in file.
 * @file	Name of file being read.
 * @file_magic	file_magic structure filled with file magic header data.
 * @rec_hdr_tmp	Temporary buffer where current record header will be saved.
 * @endian_mismatch
 *		TRUE if file's data don't match current machine's endianness.
 * @arch_64	TRUE if file's data come from a 64 bit machine.
 * @b_size	Size of @rec_hdr_tmp buffer.
 *
 * OUT:
 * @curr	Index in array for next sample statistics.
 * @cnt		Number of remaining lines of stats to write.
 * @eosaf	Set to TRUE if EOF (end of file) has been reached.
 * @reset	Set to TRUE if last_uptime variable should be reinitialized
 *		(used in next_slice() function).
 ***************************************************************************
 */
void handle_curr_act_stats(int ifd, off_t fpos, int *curr, long *cnt, int *eosaf,
			   int rows, unsigned int act_id, int *reset,
			   struct file_activity *file_actlst, char *file,
			   struct file_magic *file_magic, void *rec_hdr_tmp,
			   int endian_mismatch, int arch_64, size_t b_size)
{
	int p, reset_cd;
	unsigned long lines = 0;
	unsigned char rtype;
	int davg = 0, next, inc = 0;

	if (lseek(ifd, fpos, SEEK_SET) < fpos) {
		perror("lseek");
		exit(2);
	}

	/*
	 * Restore the first stats collected.
	 * Used to compute the rate displayed on the first line.
	 */
	copy_structures(act, id_seq, record_hdr, !*curr, 2);

	*cnt  = count;

	/* Assess number of lines printed when a bitmap is used */
	p = get_activity_position(act, act_id, EXIT_IF_NOT_FOUND);
	if (act[p]->bitmap) {
		inc = count_bits(act[p]->bitmap->b_array,
				 BITMAP_SIZE(act[p]->bitmap->b_size));
	}
	reset_cd = 1;

	do {
		/*
		 * Display <count> lines of stats.
		 * Start with reading current sample's record header.
		 */
		*eosaf = read_record_hdr(ifd, rec_hdr_tmp, &record_hdr[*curr],
					 &file_hdr, arch_64, endian_mismatch, UEOF_STOP, b_size);
		rtype = record_hdr[*curr].record_type;

		if (!*eosaf && (rtype != R_RESTART) && (rtype != R_COMMENT)) {
			/* Read the extra fields since it's not a special record */
			read_file_stat_bunch(act, *curr, ifd, file_hdr.sa_act_nr, file_actlst,
					     endian_mismatch, arch_64, file, file_magic, UEOF_STOP);
		}

		if ((lines >= rows) || !lines) {
			lines = 0;
			dis = 1;
		}
		else
			dis = 0;

		if (!*eosaf && (rtype != R_RESTART)) {

			if (rtype == R_COMMENT) {
				/* Display comment */
				next = print_special_record(&record_hdr[*curr], flags + S_F_LOCAL_TIME,
							    &tm_start, &tm_end, R_COMMENT, ifd,
							    &rectime, NULL, file, 0,
							    file_magic, &file_hdr, act, &sar_fmt,
							    endian_mismatch, arch_64);
				if (next && lines) {
					/*
					 * A line of comment was actually displayed: Count it in the
					 * total number of displayed lines.
					 * If no lines of stats had been previously displayed, ignore it
					 * to make sure the header line will be displayed.
					 */
					lines++;
				}
				continue;
			}

			/* next is set to 1 when we were close enough to desired interval */
			next = write_stats(*curr, USE_SA_FILE, cnt, tm_start.use, tm_end.use,
					   *reset, act_id, reset_cd);
			reset_cd = 0;
			if (next && (*cnt > 0)) {
				(*cnt)--;
			}

			if (next) {
				davg++;
				*curr ^= 1;

				if (inc) {
					lines += inc;
				}
				else {
					lines += act[p]->nr[*curr];
				}
			}
			*reset = FALSE;
		}
	}
	while (*cnt && !*eosaf && (rtype != R_RESTART));

	if (davg) {
		write_stats_avg(!*curr, USE_SA_FILE, act_id);
	}

	*reset = TRUE;
}

/*
 ***************************************************************************
 * Read header data sent by sadc.
 ***************************************************************************
 */
void read_header_data(void)
{
	struct file_magic file_magic;
	struct file_activity file_act;
	int rc, i, p;
	char version[16];

	/* Read magic header */
	rc = sa_read(&file_magic, FILE_MAGIC_SIZE);

	sprintf(version, "%d.%d.%d.%d",
		file_magic.sysstat_version,
		file_magic.sysstat_patchlevel,
		file_magic.sysstat_sublevel,
		file_magic.sysstat_extraversion);
	if (!file_magic.sysstat_extraversion) {
		version[strlen(version) - 2] = '\0';
	}

	if (rc || (file_magic.sysstat_magic != SYSSTAT_MAGIC) ||
	    (file_magic.format_magic != FORMAT_MAGIC) ||
	    strcmp(version, VERSION)) {

		/* sar and sadc commands are not consistent */
		if (!rc && (file_magic.sysstat_magic == SYSSTAT_MAGIC)) {
			fprintf(stderr,
				_("Using a wrong data collector from a different sysstat version\n"));
		}

#ifdef DEBUG
		fprintf(stderr, "%s: sysstat_magic=%x format_magic=%x version=%s\n",
			__FUNCTION__, file_magic.sysstat_magic, file_magic.format_magic, version);
#endif
		print_read_error(INCONSISTENT_INPUT_DATA);
	}

	/*
	 * Read header data.
	 * No need to take into account file_magic.header_size. We are sure that
	 * sadc and sar are from the same version (we have checked FORMAT_MAGIC
	 * but also VERSION above) and thus the size of file_header is FILE_HEADER_SIZE.
	 */
	if (sa_read(&file_hdr, FILE_HEADER_SIZE)) {
#ifdef DEBUG
		fprintf(stderr, "%s: File header\n", __FUNCTION__);
#endif
		print_read_error(END_OF_DATA_UNEXPECTED);
	}

	/* All activities are not necessarily selected, but NR_ACT is a max */
	if (file_hdr.sa_act_nr > NR_ACT) {
#ifdef DEBUG
		fprintf(stderr, "%s: sa_act_nr=%d\n", __FUNCTION__, file_hdr.sa_act_nr);
#endif
		print_read_error(INCONSISTENT_INPUT_DATA);
	}

	if ((file_hdr.act_size != FILE_ACTIVITY_SIZE) ||
	    (file_hdr.rec_size != RECORD_HEADER_SIZE)) {
#ifdef DEBUG
		fprintf(stderr, "%s: act_size=%u/%lu rec_size=%u/%lu\n", __FUNCTION__,
			file_hdr.act_size, FILE_ACTIVITY_SIZE, file_hdr.rec_size, RECORD_HEADER_SIZE);
#endif
		print_read_error(INCONSISTENT_INPUT_DATA);
	}

	/* Read activity list */
	for (i = 0; i < file_hdr.sa_act_nr; i++) {

		if (sa_read(&file_act, FILE_ACTIVITY_SIZE)) {
#ifdef DEBUG
			fprintf(stderr, "%s: File activity (%d)\n", __FUNCTION__, i);
#endif
			print_read_error(END_OF_DATA_UNEXPECTED);
		}

		p = get_activity_position(act, file_act.id, RESUME_IF_NOT_FOUND);

		if ((p < 0) || (act[p]->fsize != file_act.size)
			    || (act[p]->gtypes_nr[0] != file_act.types_nr[0])
			    || (act[p]->gtypes_nr[1] != file_act.types_nr[1])
			    || (act[p]->gtypes_nr[2] != file_act.types_nr[2])
			    || (file_act.nr <= 0)
			    || (file_act.nr2 <= 0)
			    || (act[p]->magic != file_act.magic)) {
#ifdef DEBUG
			if (p < 0) {
				fprintf(stderr, "%s: p=%d\n", __FUNCTION__, p);
			}
			else {
				fprintf(stderr, "%s: %s: size=%d/%d magic=%x/%x nr=%d nr2=%d types=%d,%d,%d/%d,%d,%d\n",
					__FUNCTION__, act[p]->name, act[p]->fsize, file_act.size,
					act[p]->magic, file_act.magic, file_act.nr, file_act.nr2,
					act[p]->gtypes_nr[0], act[p]->gtypes_nr[1], act[p]->gtypes_nr[2],
					file_act.types_nr[0], file_act.types_nr[1], file_act.types_nr[2]);
			}
#endif
			/* Remember that we are reading data from sadc and not from a file... */
			print_read_error(INCONSISTENT_INPUT_DATA);
		}

		id_seq[i]      = file_act.id;	/* We necessarily have "i < NR_ACT" */
		act[p]->nr_ini = file_act.nr;
		act[p]->nr2    = file_act.nr2;
	}

	while (i < NR_ACT) {
		id_seq[i++] = 0;
	}

	/* Check that all selected activties are actually sent by sadc */
	reverse_check_act(file_hdr.sa_act_nr);

	return;
}

/*
 ***************************************************************************
 * Read statistics from a system activity data file.
 *
 * IN:
 * @from_file	Input file name.
 ***************************************************************************
 */
void read_stats_from_file(char from_file[])
{
	struct file_magic file_magic;
	struct file_activity *file_actlst = NULL;
	char rec_hdr_tmp[MAX_RECORD_HEADER_SIZE];
	int curr = 1, i, p;
	int ifd, rtype;
	int rows, eosaf = TRUE, reset = FALSE;
	long cnt = 1;
	off_t fpos;

	/* Get window size */
	rows = get_win_height();

	/* Read file headers and activity list */
	check_file_actlst(&ifd, from_file, act, &file_magic, &file_hdr,
			  &file_actlst, id_seq, FALSE, &endian_mismatch, &arch_64);

	/* Perform required allocations */
	allocate_structures(act);

	/* Print report header */
	print_report_hdr(flags, &rectime, &file_hdr);

	/* Read system statistics from file */
	do {
		/*
		 * If this record is a special (RESTART or COMMENT) one, print it and
		 * (try to) get another one.
		 */
		do {
			if (read_record_hdr(ifd, rec_hdr_tmp, &record_hdr[0], &file_hdr,
					    arch_64, endian_mismatch, UEOF_STOP, sizeof(rec_hdr_tmp))) {
				/* End of sa data file */
				return;
			}

			rtype = record_hdr[0].record_type;
			if ((rtype == R_RESTART) || (rtype == R_COMMENT)) {
				print_special_record(&record_hdr[0], flags + S_F_LOCAL_TIME,
						     &tm_start, &tm_end, rtype, ifd,
						     &rectime, NULL, from_file, 0, &file_magic,
						     &file_hdr, act, &sar_fmt, endian_mismatch, arch_64);
			}
			else {
				/*
				 * OK: Previous record was not a special one.
				 * So read now the extra fields.
				 */
				read_file_stat_bunch(act, 0, ifd, file_hdr.sa_act_nr,
						     file_actlst, endian_mismatch, arch_64,
						     from_file, &file_magic, UEOF_STOP);
				if (sa_get_record_timestamp_struct(flags + S_F_LOCAL_TIME,
								   &record_hdr[0],
								   &rectime, NULL))
					/*
					 * An error was detected.
					 * The timestamp hasn't been updated.
					 */
					continue;
			}
		}
		while ((rtype == R_RESTART) || (rtype == R_COMMENT) ||
		       (tm_start.use && (datecmp(&rectime, &tm_start) < 0)) ||
		       (tm_end.use && (datecmp(&rectime, &tm_end) >=0)));

		/* Save the first stats collected. Will be used to compute the average */
		copy_structures(act, id_seq, record_hdr, 2, 0);

		reset = TRUE;	/* Set flag to reset last_uptime variable */

		/* Save current file position */
		if ((fpos = lseek(ifd, 0, SEEK_CUR)) < 0) {
			perror("lseek");
			exit(2);
		}

		/*
		 * Read and write stats located between two possible Linux restarts.
		 * Activities that should be displayed are saved in id_seq[] array.
		 * Since we are reading from a file, we print all the stats for an
		 * activity before displaying the next activity.
		 * id_seq[] has been created in check_file_actlst(), retaining only
		 * activities known by current sysstat version.
		 */
		for (i = 0; i < NR_ACT; i++) {

			if (!id_seq[i])
				continue;

			p = get_activity_position(act, id_seq[i], EXIT_IF_NOT_FOUND);
			if (!IS_SELECTED(act[p]->options))
				continue;

			if (!HAS_MULTIPLE_OUTPUTS(act[p]->options)) {
				handle_curr_act_stats(ifd, fpos, &curr, &cnt, &eosaf, rows,
						      act[p]->id, &reset, file_actlst,
						      from_file, &file_magic, rec_hdr_tmp,
						      endian_mismatch, arch_64, sizeof(rec_hdr_tmp));
			}
			else {
				unsigned int optf, msk;

				optf = act[p]->opt_flags;

				for (msk = 1; msk < 0x100; msk <<= 1) {
					if ((act[p]->opt_flags & 0xff) & msk) {
						act[p]->opt_flags &= (0xffffff00 + msk);

						handle_curr_act_stats(ifd, fpos, &curr, &cnt, &eosaf,
								      rows, act[p]->id, &reset, file_actlst,
								      from_file, &file_magic, rec_hdr_tmp,
								      endian_mismatch, arch_64, sizeof(rec_hdr_tmp));
						act[p]->opt_flags = optf;
					}
				}
			}
		}

		if (!cnt) {
			/* Go to next Linux restart, if possible */
			do {
				/* Read next record header */
				eosaf = read_record_hdr(ifd, rec_hdr_tmp, &record_hdr[curr],
							&file_hdr, arch_64, endian_mismatch, UEOF_STOP, sizeof(rec_hdr_tmp));
				rtype = record_hdr[curr].record_type;

				if (!eosaf && (rtype != R_RESTART) && (rtype != R_COMMENT)) {
					read_file_stat_bunch(act, curr, ifd, file_hdr.sa_act_nr,
							     file_actlst, endian_mismatch, arch_64,
							     from_file, &file_magic, UEOF_STOP);
				}
				else if (!eosaf && (rtype == R_COMMENT)) {
					/* This was a COMMENT record: print it */
					print_special_record(&record_hdr[curr], flags + S_F_LOCAL_TIME,
							     &tm_start, &tm_end, R_COMMENT, ifd,
							     &rectime, NULL, from_file, 0,
							     &file_magic, &file_hdr, act, &sar_fmt,
							     endian_mismatch, arch_64);
				}
			}
			while (!eosaf && (rtype != R_RESTART));
		}

		/* The last record we read was a RESTART one: Print it */
		if (!eosaf && (record_hdr[curr].record_type == R_RESTART)) {
			print_special_record(&record_hdr[curr], flags + S_F_LOCAL_TIME,
					     &tm_start, &tm_end, R_RESTART, ifd,
					     &rectime, NULL, from_file, 0,
					     &file_magic, &file_hdr, act, &sar_fmt,
					     endian_mismatch, arch_64);
		}
	}
	while (!eosaf);

	close(ifd);

	free(file_actlst);
}

/*
 ***************************************************************************
 * Read statistics sent by sadc, the data collector.
 ***************************************************************************
 */
void read_stats(void)
{
	int curr = 1;
	unsigned long lines;
	unsigned int rows;
	int dis_hdr = 0;

	/* Don't buffer data if redirected to a pipe... */
	setbuf(stdout, NULL);

	/* Read stats header */
	read_header_data();

	if (!get_activity_nr(act, AO_SELECTED, COUNT_ACTIVITIES)) {
		/* Requested activities not available: Exit */
		print_collect_error();
	}

	/* Determine if a stat line header has to be displayed */
	dis_hdr = check_line_hdr();

	lines = rows = get_win_height();

	/* Perform required allocations */
	allocate_structures(act);

	/* Print report header */
	print_report_hdr(flags, &rectime, &file_hdr);

	/* Read system statistics sent by the data collector */
	read_sadc_stat_bunch(0);

	if (!interval) {
		/* Display stats since boot time and exit */
		write_stats_startup(0);
	}

	/* Save the first stats collected. Will be used to compute the average */
	copy_structures(act, id_seq, record_hdr, 2, 0);

	/* Set a handler for SIGINT */
	memset(&int_act, 0, sizeof(int_act));
	int_act.sa_handler = int_handler;
	int_act.sa_flags = SA_RESTART;
	sigaction(SIGINT, &int_act, NULL);

	/* Main loop */
	do {

		/* Get stats */
		read_sadc_stat_bunch(curr);
		if (sigint_caught) {
			/*
			 * SIGINT signal caught (it is sent by sadc).
			 * => Display average stats.
			 */
			curr ^= 1; /* No data retrieved from last read */
			break;
		}

		/* Print results */
		if (!dis_hdr) {
			dis = lines / rows;
			if (dis) {
				lines %= rows;
			}
			lines++;
		}
		write_stats(curr, USE_SADC, &count, NO_TM_START, tm_end.use,
			    NO_RESET, ALL_ACTIVITIES, TRUE);

		if (record_hdr[curr].record_type == R_LAST_STATS) {
			/* File rotation is happening: Re-read header data sent by sadc */
			read_header_data();
			allocate_structures(act);
		}

		if (count > 0) {
			count--;
		}
		if (count) {
			curr ^= 1;
		}
	}
	while (count);

	/*
	 * Print statistics average.
	 * At least one line of stats must have been displayed for this.
	 * (There may be no lines at all if we press Ctrl/C immediately).
	 */
	dis = dis_hdr;
	if (avg_count) {
		write_stats_avg(curr, USE_SADC, ALL_ACTIVITIES);
	}
}

/*
 ***************************************************************************
 * Main entry to the sar program.
 ***************************************************************************
 */
int main(int argc, char **argv)
{
	int i, rc, opt = 1, args_idx = 1, p, q;
	int fd[2];
	int day_offset = 0;
	char from_file[MAX_FILE_LEN], to_file[MAX_FILE_LEN];
	char ltemp[1024];

	/* Compute page shift in kB */
	get_kb_shift();

	from_file[0] = to_file[0] = '\0';

#ifdef USE_NLS
	/* Init National Language Support */
	init_nls();
#endif

	/* Init color strings */
	init_colors();

	tm_start.use = tm_end.use = FALSE;

	/* Allocate and init activity bitmaps */
	allocate_bitmaps(act);

	init_structures();

	/* Process options */
	while (opt < argc) {

		if (!strcmp(argv[opt], "--sadc")) {
			/* Locate sadc */
			which_sadc();
		}

		else if (!strncmp(argv[opt], "--dev=", 6)) {
			/* Parse devices entered on the command line */
			p = get_activity_position(act, A_DISK, EXIT_IF_NOT_FOUND);
			parse_sa_devices(argv[opt], act[p], MAX_DEV_LEN, &opt, 6);
		}

		else if (!strncmp(argv[opt], "--fs=", 5)) {
			/* Parse devices entered on the command line */
			p = get_activity_position(act, A_FS, EXIT_IF_NOT_FOUND);
			parse_sa_devices(argv[opt], act[p], MAX_FS_LEN, &opt, 5);
		}

		else if (!strncmp(argv[opt], "--iface=", 8)) {
			/* Parse devices entered on the command line */
			p = get_activity_position(act, A_NET_DEV, EXIT_IF_NOT_FOUND);
			parse_sa_devices(argv[opt], act[p], MAX_IFACE_LEN, &opt, 8);
			q = get_activity_position(act, A_NET_EDEV, EXIT_IF_NOT_FOUND);
			act[q]->item_list = act[p]->item_list;
			act[q]->item_list_sz = act[p]->item_list_sz;
			act[q]->options |= AO_LIST_ON_CMDLINE;
		}

		else if (!strcmp(argv[opt], "--help")) {
			/* Display help message */
			display_help(argv[0]);
		}

		else if (!strcmp(argv[opt], "--human")) {
			/* Display sizes in a human readable format */
			flags |= S_F_UNIT;
			opt++;
		}

		else if (!strncmp(argv[opt], "--dec=", 6) && (strlen(argv[opt]) == 7)) {
			/* Get number of decimal places */
			dplaces_nr = atoi(argv[opt] + 6);
			if ((dplaces_nr < 0) || (dplaces_nr > 2)) {
				usage(argv[0]);
			}
			opt++;
		}

		else if (!strcmp(argv[opt], "-I")) {
			/* Parse -I option */
			if (parse_sar_I_opt(argv, &opt, act)) {
				usage(argv[0]);
			}
		}

		else if (!strcmp(argv[opt], "-D")) {
			/* Option to tell sar to write to saYYYYMMDD data files */
			flags |= S_F_SA_YYYYMMDD;
			opt++;
		}

		else if (!strcmp(argv[opt], "-P")) {
			/* Parse -P option */
			if (parse_sa_P_opt(argv, &opt, &flags, act)) {
				usage(argv[0]);
			}
		}

		else if (!strcmp(argv[opt], "-o")) {
			if (to_file[0]) {
				/* Output file already specified */
				usage(argv[0]);
			}
			/* Save stats to a file */
			if ((argv[++opt]) && strncmp(argv[opt], "-", 1) &&
			    (strspn(argv[opt], DIGITS) != strlen(argv[opt]))) {
				strncpy(to_file, argv[opt++], MAX_FILE_LEN);
				to_file[MAX_FILE_LEN - 1] = '\0';
			}
			else {
				strcpy(to_file, "-");
			}
		}

		else if (!strcmp(argv[opt], "-f")) {
			if (from_file[0] || day_offset) {
				/* Input file already specified */
				usage(argv[0]);
			}
			/* Read stats from a file */
			if ((argv[++opt]) && strncmp(argv[opt], "-", 1) &&
			    (strspn(argv[opt], DIGITS) != strlen(argv[opt]))) {
				strncpy(from_file, argv[opt++], MAX_FILE_LEN);
				from_file[MAX_FILE_LEN - 1] = '\0';
				/* Check if this is an alternate directory for sa files */
				check_alt_sa_dir(from_file, day_offset, -1);
			}
			else {
				set_default_file(from_file, day_offset, -1);
			}
		}

		else if (!strcmp(argv[opt], "-s")) {
			/* Get time start */
			if (parse_timestamp(argv, &opt, &tm_start, DEF_TMSTART)) {
				usage(argv[0]);
			}
		}

		else if (!strcmp(argv[opt], "-e")) {
			/* Get time end */
			if (parse_timestamp(argv, &opt, &tm_end, DEF_TMEND)) {
				usage(argv[0]);
			}
		}

		else if (!strcmp(argv[opt], "-i")) {
			if (!argv[++opt] || (strspn(argv[opt], DIGITS) != strlen(argv[opt]))) {
				usage(argv[0]);
			}
			interval = atol(argv[opt++]);
			if (interval < 1) {
				usage(argv[0]);
			}
			flags |= S_F_INTERVAL_SET;
		}

		else if (!strcmp(argv[opt], "-m")) {
			if (!argv[++opt]) {
				usage(argv[0]);
			}
			/* Parse option -m */
			if (parse_sar_m_opt(argv, &opt, act)) {
				usage(argv[0]);
			}
		}

		else if (!strcmp(argv[opt], "-n")) {
			if (!argv[++opt]) {
				usage(argv[0]);
			}
			/* Parse option -n */
			if (parse_sar_n_opt(argv, &opt, act)) {
				usage(argv[0]);
			}
		}

		else if ((strlen(argv[opt]) > 1) &&
			 (strlen(argv[opt]) < 4) &&
			 !strncmp(argv[opt], "-", 1) &&
			 (strspn(argv[opt] + 1, DIGITS) == (strlen(argv[opt]) - 1))) {
			if (from_file[0] || day_offset) {
				/* Input file already specified */
				usage(argv[0]);
			}
			day_offset = atoi(argv[opt++] + 1);
		}

		else if (!strncmp(argv[opt], "-", 1)) {
			/* Other options not previously tested */
			if ((rc = parse_sar_opt(argv, &opt, act, &flags, C_SAR)) != 0) {
				if (rc == 1) {
					usage(argv[0]);
				}
				exit(1);
			}
			opt++;
		}

		else if (interval < 0) {
			/* Get interval */
			if (strspn(argv[opt], DIGITS) != strlen(argv[opt])) {
				usage(argv[0]);
			}
			interval = atol(argv[opt++]);
			if (interval < 0) {
				usage(argv[0]);
			}
		}

		else {
			/* Get count value */
			if ((strspn(argv[opt], DIGITS) != strlen(argv[opt])) ||
			    !interval) {
				usage(argv[0]);
			}
			if (count) {
				/* Count parameter already set */
				usage(argv[0]);
			}
			count = atol(argv[opt++]);
			if (count < 1) {
				usage(argv[0]);
			}
		}
	}

	/* 'sar' is equivalent to 'sar -f' */
	if ((argc == 1) ||
	    ((interval < 0) && !from_file[0] && !to_file[0])) {
		set_default_file(from_file, day_offset, -1);
	}

	if (tm_start.use && tm_end.use && (tm_end.tm_hour < tm_start.tm_hour)) {
		tm_end.tm_hour += 24;
	}

	/*
	 * Check option dependencies.
	 */
	/* You read from a file OR you write to it... */
	if (from_file[0] && to_file[0]) {
		fprintf(stderr, _("-f and -o options are mutually exclusive\n"));
		exit(1);
	}
	/* Use time start or option -i only when reading stats from a file */
	if ((tm_start.use || INTERVAL_SET(flags)) && !from_file[0]) {
		fprintf(stderr,
			_("Not reading from a system activity file (use -f option)\n"));
		exit(1);
	}
	/* Don't print stats since boot time if -o or -f options are used */
	if (!interval && (from_file[0] || to_file[0])) {
		usage(argv[0]);
	}

	/* Cannot enter a day shift with -o option */
	if (to_file[0] && day_offset) {
		usage(argv[0]);
	}

	if (USE_PRETTY_OPTION(flags)) {
		dm_major = get_devmap_major();
	}

	if (!count) {
		/*
		 * count parameter not set: Display all the contents of the file
		 * or generate a report continuously.
		 */
		count = -1;
	}

	/* Default is CPU activity... */
	select_default_activity(act);

	/* Check S_TIME_FORMAT variable contents */
	if (!is_iso_time_fmt())
		flags |= S_F_PREFD_TIME_OUTPUT;

	/* Reading stats from file: */
	if (from_file[0]) {
		if (interval < 0) {
			interval = 1;
		}

		/* Read stats from file */
		read_stats_from_file(from_file);

		/* Free stuctures and activity bitmaps */
		free_bitmaps(act);
		free_structures(act);

		return 0;
	}

	/* Reading stats from sadc: */

	/* Create anonymous pipe */
	if (pipe(fd) == -1) {
		perror("pipe");
		exit(4);
	}

	switch (fork()) {

	case -1:
		perror("fork");
		exit(4);
		break;

	case 0: /* Child */
		if (dup2(fd[1], STDOUT_FILENO) < 0) {
			perror("dup2");
			exit(4);
		}
		CLOSE_ALL(fd);

		/*
		 * Prepare options for sadc.
		 */
		/* Program name */
		salloc(0, SADC);

		/* Interval value */
		if (interval < 0) {
			usage(argv[0]);
		}
		else if (!interval) {
			strcpy(ltemp, "1");
			/*
			 * Display stats since system startup: Set <interval> to 1.
			 * <count> arg will also be set to 1 below.
			 */
			salloc(args_idx++, ltemp);
		}
		else {
			sprintf(ltemp, "%ld", interval);
		}
		salloc(args_idx++, ltemp);

		/* Count number */
		if (count >= 0) {
			sprintf(ltemp, "%ld", count + 1);
			salloc(args_idx++, ltemp);
		}

		/* Flags to be passed to sadc */
		salloc(args_idx++, "-Z");

		/* Writing data to a file (option -o) */
		if (to_file[0]) {
			/* Set option -D if entered */
			if (USE_SA_YYYYMMDD(flags)) {
				salloc(args_idx++, "-D");
			}
			/* Collect all possible activities (option -S XALL for sadc) */
			salloc(args_idx++, "-S");
			salloc(args_idx++, K_XALL);
			/* Outfile arg */
			salloc(args_idx++, to_file);
		}
		else {
			/*
			 * If option -o hasn't been used, then tell sadc
			 * to collect only activities that will be displayed.
			 */
			salloc(args_idx++, "-S");
			strcpy(ltemp, K_A_NULL);
			for (i = 0; i < NR_ACT; i++) {
				if (IS_SELECTED(act[i]->options)) {
					strcat(ltemp, ",");
					strcat(ltemp, act[i]->name);
				}
			}
			salloc(args_idx++, ltemp);
		}

		/* Last arg is NULL */
		args[args_idx] = NULL;

		/* Call now the data collector */
#ifdef DEBUG
		fprintf(stderr, "%s: 1.sadc: %s\n", __FUNCTION__, SADC_PATH);
#endif

		execv(SADC_PATH, args);
#ifdef DEBUG
		fprintf(stderr, "%s: 2.sadc: %s\n", __FUNCTION__, SADC);
#endif
		execvp(SADC, args);
		/*
		 * Note: Don't use execl/execlp since we don't have a fixed number of
		 * args to give to sadc.
		 */
		fprintf(stderr, _("Cannot find the data collector (%s)\n"), SADC);
		perror("exec");
		exit(4);
		break;

	default: /* Parent */
		if (dup2(fd[0], STDIN_FILENO) < 0) {
			perror("dup2");
			exit(4);
		}
		CLOSE_ALL(fd);

		/* Get now the statistics */
		read_stats();

		break;
	}

	/* Free structures and activity bitmaps */
	free_bitmaps(act);
	free_structures(act);

	return 0;
}
