granicus.if.org Git - sysstat/blob - tapestat.c

   1 /*
   2  * tapestat: report tape statistics
   3  * (C) 2015 Hewlett-Packard Development Company, L.P.
   4  *
   5  * Initial revision by Shane M. SEYMOUR (shane.seymour <at> hpe.com)
   6  * Modified for sysstat by Sebastien GODARD (sysstat <at> orange.fr)
   7  *
   8  ***************************************************************************
   9  * This program is free software; you can redistribute it and/or modify it *
  10  * under the terms of the GNU General Public License as published  by  the *
  11  * Free Software Foundation; either version 2 of the License, or (at  your *
  12  * option) any later version.                                              *
  13  *                                                                         *
  14  * This program is distributed in the hope that it  will  be  useful,  but *
  15  * WITHOUT ANY WARRANTY; without the implied warranty  of  MERCHANTABILITY *
  16  * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License *
  17  * for more details.                                                       *
  18  *                                                                         *
  19  * You should have received a copy of the GNU General Public License along *
  20  * with this program; if not, write to the Free Software Foundation, Inc., *
  21  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335 USA              *
  22  ***************************************************************************
  23  */
  24
  25 #include <stdio.h>
  26 #include <string.h>
  27 #include <stdlib.h>
  28 #include <unistd.h>
  29 #include <time.h>
  30 #include <dirent.h>
  31 #define __DO_NOT_DEFINE_COMPILE
  32 #include <regex.h>
  33 #include <inttypes.h>
  34 #include <stdint.h>
  35 #include <signal.h>
  36 #include <sys/stat.h>
  37 #include <sys/time.h>
  38 #include <sys/utsname.h>
  39
  40 #ifdef HAVE_SYS_PARAM_H
  41 #include <sys/param.h>
  42 #undef HZ /* sys/param.h defines HZ but needed for MAXPATHLEN */
  43 #endif
  44 #ifndef MAXPATHLEN
  45 #define MAXPATHLEN 256
  46 #endif
  47
  48 #include "version.h"
  49 #include "tapestat.h"
  50 #include "common.h"
  51 #include "count.h"
  52
  53 #ifdef USE_NLS
  54 #include <locale.h>
  55 #include <libintl.h>
  56 #define _(string) gettext(string)
  57 #else
  58 #define _(string) (string)
  59 #endif
  60
  61 #define SCCSID "@(#)sysstat-" VERSION ": " __FILE__ " compiled " __DATE__ " " __TIME__
  62 char *sccsid(void) { return (SCCSID); }
  63
  64 int cpu_nr = 0;         /* Nb of processors on the machine */
  65 int flags = 0;          /* Flag for common options and system state */
  66
  67 long interval = 0;
  68 char timestamp[TIMESTAMP_LEN];
  69
  70 struct sigaction alrm_act;
  71
  72 /*
  73  * For tape stats - it would be extremely rare for there to be a very large
  74  * number of tape drives attached to a system. I wouldn't expect to see more
  75  * than 20-30 in a very large configuration and discontinguous ones should
  76  * be even more rare. Because of this we keep the old and new data in a
  77  * simple data structure with the tape index being the number after the tape
  78  * drive, st0 at index 0, etc.
  79  */
  80 int max_tape_drives = 0;
  81 struct tape_stats *tape_new_stats = { NULL };
  82 struct tape_stats *tape_old_stats = { NULL };
  83 regex_t tape_reg;
  84
  85 /*
  86  ***************************************************************************
  87  * Print usage and exit.
  88  *
  89  * IN:
  90  * @progname    Name of sysstat command.
  91  ***************************************************************************
  92  */
  93 void usage(char *progname)
  94 {
  95         fprintf(stderr, _("Usage: %s [ options ] [ <interval> [ <count> ] ]\n"),
  96                 progname);
  97         fprintf(stderr, _("Options are:\n"
  98                           "[ -k | -m ] [ -t ] [ -V ] [ -y ] [ -z ]\n"));
  99         exit(1);
 100 }
 101
 102 /*
 103  ***************************************************************************
 104  * SIGALRM signal handler. No need to reset the handler here.
 105  *
 106  * IN:
 107  * @sig Signal number.
 108  ***************************************************************************
 109  */
 110 void alarm_handler(int sig)
 111 {
 112         alarm(interval);
 113 }
 114
 115 /*
 116  ***************************************************************************
 117  * Initialization.
 118  ***************************************************************************
 119  */
 120 void tape_initialise(void)
 121 {
 122         /* How many processors on this machine? */
 123         cpu_nr = get_cpu_nr(~0, FALSE);
 124
 125         /* Compile regular expression for tape names */
 126         if (regcomp(&tape_reg, "^st[0-9]+$", REG_EXTENDED) != 0) {
 127                 exit(1);
 128         }
 129 }
 130
 131 /*
 132  ***************************************************************************
 133  * Free structures.
 134  ***************************************************************************
 135  */
 136 void tape_uninitialise(void)
 137 {
 138         regfree(&tape_reg);
 139         if (tape_old_stats != NULL) {
 140                 free(tape_old_stats);
 141         }
 142         if (tape_new_stats != NULL) {
 143                 free(tape_new_stats);
 144         }
 145 }
 146
 147 /*
 148  ***************************************************************************
 149  * Get maximum number of tapes in the system.
 150  *
 151  * RETURNS:
 152  * Number of tapes found.
 153  ***************************************************************************
 154  */
 155 int get_max_tape_drives(void)
 156 {
 157         DIR *dir;
 158         struct dirent *entry;
 159         int new_max_tape_drives, tmp, num_stats_dir = 0;
 160         regmatch_t match;
 161         char stats_dir[MAXPATHLEN + 1];
 162         struct stat stat_buf;
 163
 164         new_max_tape_drives = max_tape_drives;
 165
 166         /* Open sysfs tree */
 167         dir = opendir(SYSFS_CLASS_TAPE_DIR);
 168         if (dir == NULL)
 169                 return 0;
 170
 171         while ((entry = readdir(dir)) != NULL) {
 172                 if (regexec(&tape_reg, &entry->d_name[0], 1, &match, 0) == 0) {
 173                         /* d_name[2] to skip the st at the front */
 174                         tmp = atoi(&entry->d_name[2]) + 1;
 175                         if (tmp > new_max_tape_drives) {
 176                                 new_max_tape_drives = tmp;
 177                         }
 178                 }
 179                 snprintf(stats_dir, MAXPATHLEN, "%s/%s/%s",
 180                         SYSFS_CLASS_TAPE_DIR, &entry->d_name[0], "stats");
 181                 if (stat(stats_dir, &stat_buf) == 0) {
 182                         if (S_ISDIR(stat_buf.st_mode)) {
 183                                 num_stats_dir++;
 184                         }
 185                 }
 186         }
 187         closedir(dir);
 188
 189         /* If there are no stats directories make the new number of tape drives 0 */
 190         if (num_stats_dir == 0) {
 191                 new_max_tape_drives = 0;
 192         }
 193
 194         return new_max_tape_drives;
 195 }
 196
 197 /*
 198  ***************************************************************************
 199  * Check if new tapes have been added and reallocate structures accordingly.
 200  ***************************************************************************
 201  */
 202 void tape_check_tapes_and_realloc(void)
 203 {
 204         int new_max_tape_drives, i;
 205
 206         /* Count again number of tapes */
 207         new_max_tape_drives = get_max_tape_drives();
 208
 209         if (new_max_tape_drives > max_tape_drives && new_max_tape_drives > 0) {
 210                 /* New tapes found: Realloc structures */
 211                 struct tape_stats *tape_old_stats_t = (struct tape_stats *)
 212                         realloc(tape_old_stats, sizeof(struct tape_stats) * new_max_tape_drives);
 213                 struct tape_stats *tape_new_stats_t = (struct tape_stats *)
 214                         realloc(tape_new_stats, sizeof(struct tape_stats) * new_max_tape_drives);
 215                 if ((tape_old_stats_t == NULL) || (tape_new_stats_t == NULL)) {
 216                         if (tape_old_stats_t != NULL) {
 217                                 free(tape_old_stats_t);
 218                                 tape_old_stats_t = NULL;
 219                         } else {
 220                                 free(tape_old_stats);
 221                                 tape_old_stats = NULL;
 222                         }
 223                         if (tape_new_stats_t != NULL) {
 224                                 free(tape_new_stats_t);
 225                                 tape_new_stats_t = NULL;
 226                         } else {
 227                                 free(tape_new_stats);
 228                                 tape_new_stats = NULL;
 229                         }
 230
 231                         perror("realloc");
 232                         exit(4);
 233                 }
 234
 235                 tape_old_stats = tape_old_stats_t;
 236                 tape_new_stats = tape_new_stats_t;
 237
 238                 for (i = max_tape_drives; i < new_max_tape_drives; i++) {
 239                         tape_old_stats[i].valid = TAPE_STATS_INVALID;
 240                         tape_new_stats[i].valid = TAPE_STATS_INVALID;
 241                 }
 242                 max_tape_drives = new_max_tape_drives;
 243         }
 244 }
 245
 246 /*
 247  ***************************************************************************
 248  * Collect initial statistics for all existing tapes in the system.
 249  * This function should be called only once.
 250  ***************************************************************************
 251  */
 252 void tape_gather_initial_stats(void)
 253 {
 254         int new_max_tape_drives, i;
 255         FILE *fp;
 256         char filename[MAXPATHLEN + 1];
 257
 258         /* Get number of tapes in the system */
 259         new_max_tape_drives = get_max_tape_drives();
 260
 261         if (new_max_tape_drives == 0) {
 262                 /* No tapes found */
 263                 fprintf(stderr, _("No tape drives with statistics found\n"));
 264                 exit(1);
 265         }
 266         else {
 267                 /* Allocate structures */
 268                 if (tape_old_stats == NULL) {
 269                         tape_old_stats = (struct tape_stats *)
 270                                 malloc(sizeof(struct tape_stats) * new_max_tape_drives);
 271                         tape_new_stats = (struct tape_stats *)
 272                                 malloc(sizeof(struct tape_stats) * new_max_tape_drives);
 273                         for (i = 0; i < new_max_tape_drives; i++) {
 274                                 tape_old_stats[i].valid = TAPE_STATS_INVALID;
 275                                 tape_new_stats[i].valid = TAPE_STATS_INVALID;
 276                         }
 277                         max_tape_drives = new_max_tape_drives;
 278                 } else
 279                         /* This should only be called once */
 280                         return;
 281         }
 282
 283         /* Read stats for each tape */
 284         for (i = 0; i < max_tape_drives; i++) {
 285                 /*
 286                  * Everything starts out valid but failing to open
 287                  * a file gets the tape drive marked invalid.
 288                  */
 289                 tape_new_stats[i].valid = TAPE_STATS_VALID;
 290                 tape_old_stats[i].valid = TAPE_STATS_VALID;
 291
 292                 gettimeofday(&tape_old_stats[i].tv, NULL);
 293
 294                 tape_new_stats[i].tv.tv_sec = tape_old_stats[i].tv.tv_sec;
 295                 tape_new_stats[i].tv.tv_usec = tape_old_stats[i].tv.tv_usec;
 296
 297                 TAPE_STAT_FILE_VAL(TAPE_STAT_PATH "read_ns", read_time)
 298                 TAPE_STAT_FILE_VAL(TAPE_STAT_PATH "write_ns", write_time)
 299                 TAPE_STAT_FILE_VAL(TAPE_STAT_PATH "io_ns", other_time)
 300                 TAPE_STAT_FILE_VAL(TAPE_STAT_PATH "read_byte_cnt", read_bytes)
 301                 TAPE_STAT_FILE_VAL(TAPE_STAT_PATH "write_byte_cnt", write_bytes)
 302                 TAPE_STAT_FILE_VAL(TAPE_STAT_PATH "read_cnt", read_count)
 303                 TAPE_STAT_FILE_VAL(TAPE_STAT_PATH "write_cnt", write_count)
 304                 TAPE_STAT_FILE_VAL(TAPE_STAT_PATH "other_cnt", other_count)
 305                 TAPE_STAT_FILE_VAL(TAPE_STAT_PATH "resid_cnt", resid_count)
 306
 307                 tape_old_stats[i].read_time = 0;
 308                 tape_old_stats[i].write_time = 0;
 309                 tape_old_stats[i].other_time = 0;
 310                 tape_old_stats[i].read_bytes = 0;
 311                 tape_old_stats[i].write_bytes = 0;
 312                 tape_old_stats[i].read_count = 0;
 313                 tape_old_stats[i].write_count = 0;
 314                 tape_old_stats[i].other_count = 0;
 315                 tape_old_stats[i].resid_count = 0;
 316         }
 317 }
 318
 319 /*
 320  ***************************************************************************
 321  * Collect a new sample of statistics for all existing tapes in the system.
 322  ***************************************************************************
 323  */
 324 void tape_get_updated_stats(void)
 325 {
 326         int i;
 327         FILE *fp;
 328         char filename[MAXPATHLEN + 1] = { 0 };
 329
 330         /* Check tapes and realloc structures if  needed */
 331         tape_check_tapes_and_realloc();
 332
 333         for (i = 0; i < max_tape_drives; i++) {
 334                 /*
 335                  * Everything starts out valid but failing
 336                  * to open a file gets the tape drive marked invalid.
 337                  */
 338                 tape_new_stats[i].valid = TAPE_STATS_VALID;
 339                 gettimeofday(&tape_new_stats[i].tv, NULL);
 340
 341                 TAPE_STAT_FILE_VAL(TAPE_STAT_PATH "read_ns", read_time)
 342                 TAPE_STAT_FILE_VAL(TAPE_STAT_PATH "write_ns", write_time)
 343                 TAPE_STAT_FILE_VAL(TAPE_STAT_PATH "io_ns", other_time)
 344                 TAPE_STAT_FILE_VAL(TAPE_STAT_PATH "read_byte_cnt", read_bytes)
 345                 TAPE_STAT_FILE_VAL(TAPE_STAT_PATH "write_byte_cnt", write_bytes)
 346                 TAPE_STAT_FILE_VAL(TAPE_STAT_PATH "read_cnt", read_count)
 347                 TAPE_STAT_FILE_VAL(TAPE_STAT_PATH "write_cnt", write_count)
 348                 TAPE_STAT_FILE_VAL(TAPE_STAT_PATH "other_cnt", other_count)
 349                 TAPE_STAT_FILE_VAL(TAPE_STAT_PATH "resid_cnt", resid_count)
 350
 351                 if ((tape_new_stats[i].read_time < tape_old_stats[i].read_time) ||
 352                     (tape_new_stats[i].write_time < tape_old_stats[i].write_time) ||
 353                     (tape_new_stats[i].other_time < tape_old_stats[i].other_time)) {
 354                         tape_new_stats[i].valid = TAPE_STATS_INVALID;
 355                 }
 356         }
 357 }
 358
 359 /*
 360  ***************************************************************************
 361  * Display tapes statistics headings.
 362  ***************************************************************************
 363  */
 364 void tape_write_headings(void)
 365 {
 366         printf("Tape:     r/s     w/s   ");
 367         if (DISPLAY_MEGABYTES(flags)) {
 368                 printf("MB_read/s   MB_wrtn/s");
 369         } else {
 370                 printf("kB_read/s   kB_wrtn/s");
 371         }
 372         printf(" %%Rd %%Wr %%Oa    Rs/s    Ot/s\n");
 373 }
 374
 375 /*
 376  ***************************************************************************
 377  * Calculate statistics for current tape.
 378  *
 379  * IN:
 380  * @i           Index in array for current tape.
 381  *
 382  * OUT:
 383  * @stats       Statistics for current tape.
 384  ***************************************************************************
 385  */
 386 void tape_calc_one_stats(struct calc_stats *stats, int i)
 387 {
 388         uint64_t duration;
 389         double temp;
 390         FILE *fp;
 391
 392         /* Duration in ms done in ms to prevent rounding issues with using seconds */
 393         duration = (tape_new_stats[i].tv.tv_sec -
 394                 tape_old_stats[i].tv.tv_sec) * 1000;
 395         duration -= tape_old_stats[i].tv.tv_usec / 1000;
 396         duration += tape_new_stats[i].tv.tv_usec / 1000;
 397
 398         /* If duration is zero we need to calculate the ms since boot time */
 399         if (duration == 0) {
 400                 fp = fopen("/proc/uptime", "r");
 401
 402                 /*
 403                  * Get uptime from /proc/uptime and if we can't then just set duration to
 404                  * be 0 - it will mean that we don't calculate stats.
 405                  */
 406                 if (fp == NULL) {
 407                         duration = 0;
 408                 } else {
 409                         if (fscanf(fp, "%lf", &temp) != 1) {
 410                                 temp = 0;
 411                         }
 412                         duration = (uint64_t) (temp * 1000);
 413                         fclose(fp);
 414                 }
 415         }
 416
 417         /* The second value passed into the macro is the thing being calculated */
 418         CALC_STAT_CNT(read_count, reads_per_second)
 419         CALC_STAT_CNT(write_count, writes_per_second)
 420         CALC_STAT_CNT(other_count, other_per_second)
 421         CALC_STAT_KB(read_bytes, kbytes_read_per_second)
 422         CALC_STAT_KB(write_bytes, kbytes_written_per_second)
 423         CALC_STAT_PCT(read_time, read_pct_wait)
 424         CALC_STAT_PCT(write_time, write_pct_wait)
 425         CALC_STAT_PCT(other_time, all_pct_wait)
 426         CALC_STAT_CNT(resid_count, resids_per_second)
 427 }
 428
 429 /*
 430  ***************************************************************************
 431  * Display statistics for current tape.
 432  *
 433  * IN:
 434  * @tape        Statistics for current tape.
 435  * @i           Index in array for current tape.
 436  ***************************************************************************
 437  */
 438 void tape_write_stats(struct calc_stats *tape, int i)
 439 {
 440         char buffer[32];
 441         uint64_t divisor = 1;
 442
 443         if (DISPLAY_MEGABYTES(flags))
 444                 divisor = 1024;
 445
 446         sprintf(buffer, "st%i        ", i);
 447         buffer[5] = 0;
 448         cprintf_in(IS_STR, "%s", buffer, 0);
 449         cprintf_u64(2, 7,
 450                     tape->reads_per_second,
 451                     tape->writes_per_second);
 452         cprintf_u64(2, 11,
 453                     tape->kbytes_read_per_second / divisor,
 454                     tape->kbytes_written_per_second / divisor);
 455         cprintf_pc(3, 3, 0,
 456                    (double) tape->read_pct_wait,
 457                    (double) tape->write_pct_wait,
 458                    (double) tape->all_pct_wait);
 459         cprintf_u64(2, 7,
 460                     tape->resids_per_second,
 461                     tape->other_per_second);
 462         printf("\n");
 463 }
 464
 465 /*
 466  ***************************************************************************
 467  * Print everything now (stats and uptime).
 468  *
 469  * IN:
 470  * @rectime     Current date and time.
 471  ***************************************************************************
 472  */
 473 void write_stats(struct tm *rectime)
 474 {
 475         int i;
 476         struct calc_stats tape;
 477         struct tape_stats *tmp;
 478
 479         /* Test stdout */
 480         TEST_STDOUT(STDOUT_FILENO);
 481
 482         /* Print time stamp */
 483         if (DISPLAY_TIMESTAMP(flags)) {
 484                 if (DISPLAY_ISO(flags)) {
 485                         strftime(timestamp, sizeof(timestamp), "%FT%T%z", rectime);
 486                 }
 487                 else {
 488                         strftime(timestamp, sizeof(timestamp), "%x %X", rectime);
 489                 }
 490                 printf("%s\n", timestamp);
 491         }
 492
 493         /* Print the headings */
 494         tape_write_headings();
 495
 496         /*
 497          * If either new or old is invalid or the I/Os per second is 0 and
 498          * zero omit is true then we print nothing.
 499          */
 500         if (max_tape_drives > 0) {
 501
 502                 for (i = 0; i < max_tape_drives; i++) {
 503                         if ((tape_new_stats[i].valid == TAPE_STATS_VALID) &&
 504                                 (tape_old_stats[i].valid == TAPE_STATS_VALID)) {
 505                                 tape_calc_one_stats(&tape, i);
 506                                 if (!(DISPLAY_ZERO_OMIT(flags)
 507                                         && (tape.other_per_second == 0)
 508                                         && (tape.reads_per_second == 0)
 509                                         && (tape.writes_per_second == 0)
 510                                         && (tape.kbytes_read_per_second == 0)
 511                                         && (tape.kbytes_written_per_second == 0)
 512                                         && (tape.read_pct_wait == 0)
 513                                         && (tape.write_pct_wait == 0)
 514                                         && (tape.all_pct_wait == 0)
 515                                         && (tape.resids_per_second == 0))) {
 516                                         tape_write_stats(&tape, i);
 517                                 }
 518                         }
 519                 }
 520                 /*
 521                  * Swap new and old so next time we compare against the new old stats.
 522                  * If a new tape drive appears it won't appear in the output until after
 523                  * the second time we gather information about it.
 524                  */
 525                 tmp = tape_old_stats;
 526                 tape_old_stats = tape_new_stats;
 527                 tape_new_stats = tmp;
 528         }
 529         printf("\n");
 530 }
 531
 532 /*
 533  ***************************************************************************
 534  * Main loop: Read tape stats from the relevant sources and display them.
 535  *
 536  * IN:
 537  * @count       Number of lines of stats to print.
 538  * @rectime     Current date and time.
 539  ***************************************************************************
 540  */
 541 void rw_tape_stat_loop(long int count, struct tm *rectime)
 542 {
 543         struct tape_stats *tmp;
 544         int skip = 0;
 545
 546         /* Should we skip first report? */
 547         if (DISPLAY_OMIT_SINCE_BOOT(flags) && interval > 0) {
 548                 skip = 1;
 549         }
 550
 551         /* Don't buffer data if redirected to a pipe */
 552         setbuf(stdout, NULL);
 553
 554         do {
 555
 556                 if (tape_new_stats == NULL) {
 557                         tape_gather_initial_stats();
 558                 } else {
 559                         tape_get_updated_stats();
 560                 }
 561
 562                 /* Get time */
 563                 get_localtime(rectime, 0);
 564
 565                 /* Check whether we should skip first report */
 566                 if (!skip) {
 567                         /* Print results */
 568                         write_stats(rectime);
 569
 570                         if (count > 0) {
 571                                 count--;
 572                         }
 573                 }
 574                 else {
 575                         skip = 0;
 576                         tmp = tape_old_stats;
 577                         tape_old_stats = tape_new_stats;
 578                         tape_new_stats = tmp;
 579                 }
 580
 581                 if (count) {
 582                         pause();
 583                 }
 584         }
 585         while (count);
 586 }
 587
 588 /*
 589  ***************************************************************************
 590  * Main entry to the tapestat program.
 591  ***************************************************************************
 592  */
 593 int main(int argc, char **argv)
 594 {
 595         int it = 0;
 596         int opt = 1;
 597         int i;
 598         long count = 1;
 599         struct utsname header;
 600         struct tm rectime;
 601
 602 #ifdef USE_NLS
 603         /* Init National Language Support */
 604         init_nls();
 605 #endif
 606
 607         /* Init color strings */
 608         init_colors();
 609
 610         /* Get HZ */
 611         get_HZ();
 612
 613         /* Process args... */
 614         while (opt < argc) {
 615                         if (!strncmp(argv[opt], "-", 1)) {
 616                         for (i = 1; *(argv[opt] + i); i++) {
 617
 618                                 switch (*(argv[opt] + i)) {
 619
 620                                 case 'k':
 621                                         if (DISPLAY_MEGABYTES(flags)) {
 622                                                 usage(argv[0]);
 623                                         }
 624                                         /* Display stats in kB/s */
 625                                         flags |= T_D_KILOBYTES;
 626                                         break;
 627
 628                                 case 'm':
 629                                         if (DISPLAY_KILOBYTES(flags)) {
 630                                                 usage(argv[0]);
 631                                         }
 632                                         /* Display stats in MB/s */
 633                                         flags |= T_D_MEGABYTES;
 634                                         break;
 635
 636                                 case 't':
 637                                         /* Display timestamp */
 638                                         flags |= T_D_TIMESTAMP;
 639                                         break;
 640
 641                                 case 'y':
 642                                         /* Don't display stats since system restart */
 643                                         flags |= T_D_OMIT_SINCE_BOOT;
 644                                         break;
 645
 646                                 case 'z':
 647                                         /* Omit output for devices with no activity */
 648                                         flags |= T_D_ZERO_OMIT;
 649                                         break;
 650
 651                                 case 'V':
 652                                         /* Print version number and exit */
 653                                         print_version();
 654                                         break;
 655
 656                                 default:
 657                                         usage(argv[0]);
 658                                 }
 659                         }
 660                         opt++;
 661                 }
 662
 663                 else if (!it) {
 664                         interval = atol(argv[opt++]);
 665                         if (interval < 0) {
 666                                 usage(argv[0]);
 667                         }
 668                         count = -1;
 669                         it = 1;
 670                 }
 671
 672                 else if (it > 0) {
 673                         count = atol(argv[opt++]);
 674                         if ((count < 1) || !interval) {
 675                                 usage(argv[0]);
 676                         }
 677                         it = -1;
 678                 }
 679                 else {
 680                         usage(argv[0]);
 681                 }
 682         }
 683
 684         if (!interval) {
 685                 count = 1;
 686         }
 687
 688         tape_initialise();
 689
 690         get_localtime(&rectime, 0);
 691
 692         /* Get system name, release number and hostname */
 693         uname(&header);
 694         if (print_gal_header(&rectime, header.sysname, header.release,
 695                              header.nodename, header.machine, cpu_nr,
 696                              PLAIN_OUTPUT)) {
 697                 flags |= T_D_ISO;
 698         }
 699         printf("\n");
 700
 701         /* Set a handler for SIGALRM */
 702         memset(&alrm_act, 0, sizeof(alrm_act));
 703         alrm_act.sa_handler = alarm_handler;
 704         sigaction(SIGALRM, &alrm_act, NULL);
 705         alarm(interval);
 706
 707         /* Main loop */
 708         rw_tape_stat_loop(count, &rectime);
 709
 710         /* Free structures */
 711         tape_uninitialise();
 712
 713         return 0;
 714 }