savecore.c revision 1.30
1/* $NetBSD: savecore.c,v 1.30 1997/05/19 16:28:03 pk Exp $ */ 2 3/*- 4 * Copyright (c) 1986, 1992, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36#ifndef lint 37static char copyright[] = 38"@(#) Copyright (c) 1986, 1992, 1993\n\ 39 The Regents of the University of California. All rights reserved.\n"; 40#endif /* not lint */ 41 42#ifndef lint 43#if 0 44static char sccsid[] = "@(#)savecore.c 8.3 (Berkeley) 1/2/94"; 45#else 46static char rcsid[] = "$NetBSD: savecore.c,v 1.30 1997/05/19 16:28:03 pk Exp $"; 47#endif 48#endif /* not lint */ 49 50#include <sys/param.h> 51#include <sys/stat.h> 52#include <sys/mount.h> 53#include <sys/syslog.h> 54#include <sys/time.h> 55 56#include <dirent.h> 57#include <errno.h> 58#include <fcntl.h> 59#include <nlist.h> 60#include <paths.h> 61#include <stdio.h> 62#include <stdlib.h> 63#include <string.h> 64#include <tzfile.h> 65#include <unistd.h> 66#include <limits.h> 67#include <kvm.h> 68 69extern FILE *zopen __P((const char *fname, const char *mode, int bits)); 70 71#define KREAD(kd, addr, p)\ 72 (kvm_read(kd, addr, (char *)(p), sizeof(*(p))) != sizeof(*(p))) 73 74struct nlist current_nl[] = { /* Namelist for currently running system. */ 75#define X_DUMPDEV 0 76 { "_dumpdev" }, 77#define X_DUMPLO 1 78 { "_dumplo" }, 79#define X_TIME 2 80 { "_time" }, 81#define X_DUMPSIZE 3 82 { "_dumpsize" }, 83#define X_VERSION 4 84 { "_version" }, 85#define X_PANICSTR 5 86 { "_panicstr" }, 87#define X_DUMPMAG 6 88 { "_dumpmag" }, 89 { NULL }, 90}; 91int cursyms[] = { X_DUMPDEV, X_DUMPLO, X_VERSION, X_DUMPMAG, -1 }; 92int dumpsyms[] = { X_TIME, X_DUMPSIZE, X_VERSION, X_PANICSTR, X_DUMPMAG, -1 }; 93 94struct nlist dump_nl[] = { /* Name list for dumped system. */ 95 { "_dumpdev" }, /* Entries MUST be the same as */ 96 { "_dumplo" }, /* those in current_nl[]. */ 97 { "_time" }, 98 { "_dumpsize" }, 99 { "_version" }, 100 { "_panicstr" }, 101 { "_dumpmag" }, 102 { NULL }, 103}; 104 105/* Types match kernel declarations. */ 106long dumplo; /* where dump starts on dumpdev */ 107int dumpmag; /* magic number in dump */ 108int dumpsize; /* amount of memory dumped */ 109 110char *kernel; 111char *dirname; /* directory to save dumps in */ 112char *ddname; /* name of dump device */ 113dev_t dumpdev; /* dump device */ 114int dumpfd; /* read/write descriptor on block dev */ 115kvm_t *kd_dump; /* kvm descriptor on block dev */ 116time_t now; /* current date */ 117char panic_mesg[1024]; 118long panicstr; 119char vers[1024]; 120 121int clear, compress, force, verbose; /* flags */ 122 123void check_kmem __P((void)); 124int check_space __P((void)); 125void clear_dump __P((void)); 126int Create __P((char *, int)); 127int dump_exists __P((void)); 128char *find_dev __P((dev_t, int)); 129int get_crashtime __P((void)); 130void kmem_setup __P((void)); 131void log __P((int, char *, ...)); 132void Lseek __P((int, off_t, int)); 133int Open __P((char *, int rw)); 134char *rawname __P((char *s)); 135void save_core __P((void)); 136void usage __P((void)); 137void Write __P((int, void *, int)); 138 139int 140main(argc, argv) 141 int argc; 142 char *argv[]; 143{ 144 int ch; 145 146 openlog("savecore", LOG_PERROR, LOG_DAEMON); 147 148 while ((ch = getopt(argc, argv, "cdfN:vz")) != -1) 149 switch(ch) { 150 case 'c': 151 clear = 1; 152 break; 153 case 'd': /* Not documented. */ 154 case 'v': 155 verbose = 1; 156 break; 157 case 'f': 158 force = 1; 159 break; 160 case 'N': 161 kernel = optarg; 162 break; 163 case 'z': 164 compress = 1; 165 break; 166 case '?': 167 default: 168 usage(); 169 } 170 argc -= optind; 171 argv += optind; 172 173 if (!clear) { 174 if (argc != 1 && argc != 2) 175 usage(); 176 dirname = argv[0]; 177 } 178 if (argc == 2) 179 kernel = argv[1]; 180 181 (void)time(&now); 182 kmem_setup(); 183 184 if (clear) { 185 clear_dump(); 186 exit(0); 187 } 188 189 if (!dump_exists() && !force) 190 exit(1); 191 192 check_kmem(); 193 194 if (panicstr) 195 syslog(LOG_ALERT, "reboot after panic: %s", panic_mesg); 196 else 197 syslog(LOG_ALERT, "reboot"); 198 199 if ((!get_crashtime() || !check_space()) && !force) 200 exit(1); 201 202 save_core(); 203 204 clear_dump(); 205 exit(0); 206} 207 208void 209kmem_setup() 210{ 211 kvm_t *kd_kern; 212 char errbuf[_POSIX2_LINE_MAX]; 213 int i, hdrsz; 214 char *dump_sys; 215 216 /* 217 * Some names we need for the currently running system, others for 218 * the system that was running when the dump was made. The values 219 * obtained from the current system are used to look for things in 220 * /dev/kmem that cannot be found in the dump_sys namelist, but are 221 * presumed to be the same (since the disk partitions are probably 222 * the same!) 223 */ 224 kd_kern = kvm_openfiles(NULL, NULL, NULL, O_RDONLY, errbuf); 225 if (kd_kern == NULL) { 226 syslog(LOG_ERR, "%s: kvm_openfiles: %s", _PATH_UNIX, errbuf); 227 exit(1); 228 } 229 if (kvm_nlist(kd_kern, current_nl) == -1) 230 syslog(LOG_ERR, "%s: kvm_nlist: %s", _PATH_UNIX, 231 kvm_geterr(kd_kern)); 232 233 for (i = 0; cursyms[i] != -1; i++) 234 if (current_nl[cursyms[i]].n_value == 0) { 235 syslog(LOG_ERR, "%s: %s not in namelist", 236 _PATH_UNIX, current_nl[cursyms[i]].n_name); 237 exit(1); 238 } 239 240 if (KREAD(kd_kern, current_nl[X_DUMPDEV].n_value, &dumpdev) != 0) { 241 if (verbose) 242 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_kern)); 243 exit(1); 244 } 245 if (dumpdev == NODEV) { 246 syslog(LOG_WARNING, "no core dump (no dumpdev)"); 247 exit(1); 248 } 249 if (KREAD(kd_kern, current_nl[X_DUMPLO].n_value, &dumplo) != 0) { 250 if (verbose) 251 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_kern)); 252 exit(1); 253 } 254 dumplo *= DEV_BSIZE; 255 if (verbose) 256 (void)printf("dumplo = %d (%d * %d)\n", 257 dumplo, dumplo / DEV_BSIZE, DEV_BSIZE); 258 if (KREAD(kd_kern, current_nl[X_DUMPMAG].n_value, &dumpmag) != 0) { 259 if (verbose) 260 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_kern)); 261 exit(1); 262 } 263 264 if (kernel == NULL) { 265 (void)kvm_read(kd_kern, current_nl[X_VERSION].n_value, 266 vers, sizeof(vers)); 267 vers[sizeof(vers) - 1] = '\0'; 268 } 269 270 ddname = find_dev(dumpdev, S_IFBLK); 271 dumpfd = Open(ddname, O_RDWR); 272 273 dump_sys = kernel ? kernel : _PATH_UNIX; 274 275 kd_dump = kvm_openfiles(dump_sys, ddname, NULL, O_RDWR, errbuf); 276 if (kd_dump == NULL) { 277 syslog(LOG_ERR, "%s: kvm_openfiles: %s", dump_sys, errbuf); 278 exit(1); 279 } 280 281 if (kvm_nlist(kd_dump, dump_nl) == -1) 282 syslog(LOG_ERR, "%s: kvm_nlist: %s", dump_sys, 283 kvm_geterr(kd_dump)); 284 285 for (i = 0; dumpsyms[i] != -1; i++) 286 if (dump_nl[dumpsyms[i]].n_value == 0) { 287 syslog(LOG_ERR, "%s: %s not in namelist", 288 dump_sys, dump_nl[dumpsyms[i]].n_name); 289 exit(1); 290 } 291 hdrsz = kvm_dump_mkheader(kd_dump, (off_t)dumplo); 292 293 /* 294 * If 'hdrsz' == 0, kvm_dump_mkheader() failed on the magic-number 295 * checks, ergo no dump is present... 296 */ 297 if (hdrsz == 0) { 298 syslog(LOG_WARNING, "no core dump"); 299 exit(1); 300 } 301 if (hdrsz == -1) { 302 syslog(LOG_ERR, "%s: kvm_dump_mkheader: %s", dump_sys, 303 kvm_geterr(kd_dump)); 304 exit(1); 305 } 306 dumplo += hdrsz; 307 kvm_close(kd_kern); 308} 309 310void 311check_kmem() 312{ 313 register char *cp; 314 register long panicloc; 315 char core_vers[1024]; 316 317 (void)kvm_read(kd_dump, dump_nl[X_VERSION].n_value, core_vers, 318 sizeof(core_vers)); 319 core_vers[sizeof(core_vers) - 1] = '\0'; 320 321 if (strcmp(vers, core_vers) && kernel == 0) 322 syslog(LOG_WARNING, 323 "warning: %s version mismatch:\n\t%s\nand\t%s\n", 324 _PATH_UNIX, vers, core_vers); 325 326 if (KREAD(kd_dump, dump_nl[X_PANICSTR].n_value, &panicstr) != 0) { 327 if (verbose) 328 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump)); 329 return; 330 } 331 if (panicstr) { 332 cp = panic_mesg; 333 panicloc = panicstr; 334 do { 335 if (KREAD(kd_dump, panicloc, cp) != 0) { 336 if (verbose) 337 syslog(LOG_WARNING, "kvm_read: %s", 338 kvm_geterr(kd_dump)); 339 break; 340 } 341 panicloc++; 342 } while (*cp++ && cp < &panic_mesg[sizeof(panic_mesg)-1]); 343 panic_mesg[sizeof(panic_mesg) - 1] = '\0'; 344 } 345} 346 347int 348dump_exists() 349{ 350 int newdumpmag; 351 352 if (KREAD(kd_dump, dump_nl[X_DUMPMAG].n_value, &newdumpmag) != 0) { 353 if (verbose) 354 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump)); 355 return (0); 356 } 357 358 /* Read the dump size. */ 359 if (KREAD(kd_dump, dump_nl[X_DUMPSIZE].n_value, &dumpsize) != 0) { 360 if (verbose) 361 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump)); 362 return (0); 363 } 364 dumpsize *= getpagesize(); 365 366 /* 367 * Return zero if core dump doesn't seem to be there, and note 368 * it for syslog. This check and return happens after the dump size 369 * is read, so dumpsize is whether or not the core is valid (for -f). 370 */ 371 if (newdumpmag != dumpmag) { 372 if (verbose) 373 syslog(LOG_WARNING, "magic number mismatch (%x != %x)", 374 newdumpmag, dumpmag); 375 syslog(LOG_WARNING, "no core dump"); 376 return (0); 377 } 378 return (1); 379} 380 381void 382clear_dump() 383{ 384 if (kvm_dump_inval(kd_dump) == -1) 385 syslog(LOG_ERR, "%s: kvm_clear_dump: %s", ddname, 386 kvm_geterr(kd_dump)); 387 388} 389 390char buf[1024 * 1024]; 391 392void 393save_core() 394{ 395 register FILE *fp; 396 register int bounds, ifd, nr, nw, ofd; 397 char *rawp, path[MAXPATHLEN]; 398 399 /* 400 * Get the current number and update the bounds file. Do the update 401 * now, because may fail later and don't want to overwrite anything. 402 */ 403 umask(002); 404 (void)snprintf(path, sizeof(path), "%s/bounds", dirname); 405 if ((fp = fopen(path, "r")) == NULL) 406 goto err1; 407 if (fgets(buf, sizeof(buf), fp) == NULL) { 408 if (ferror(fp)) 409err1: syslog(LOG_WARNING, "%s: %s", path, strerror(errno)); 410 bounds = 0; 411 } else 412 bounds = atoi(buf); 413 if (fp != NULL) 414 (void)fclose(fp); 415 if ((fp = fopen(path, "w")) == NULL) 416 syslog(LOG_ERR, "%s: %m", path); 417 else { 418 (void)fprintf(fp, "%d\n", bounds + 1); 419 (void)fclose(fp); 420 } 421 (void)fclose(fp); 422 423 /* Create the core file. */ 424 (void)snprintf(path, sizeof(path), "%s/netbsd.%d.core%s", 425 dirname, bounds, compress ? ".Z" : ""); 426 if (compress) { 427 if ((fp = zopen(path, "w", 0)) == NULL) { 428 syslog(LOG_ERR, "%s: %s", path, strerror(errno)); 429 exit(1); 430 } 431 } else { 432 ofd = Create(path, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH); 433 fp = fdopen(ofd, "w"); 434 if (fp == NULL) { 435 syslog(LOG_ERR, "%s: fdopen: %s", path); 436 exit(1); 437 } 438 } 439 440 /* Open the raw device. */ 441 rawp = rawname(ddname); 442 if ((ifd = open(rawp, O_RDONLY)) == -1) { 443 syslog(LOG_WARNING, "%s: %m; using block device", rawp); 444 ifd = dumpfd; 445 } 446 447 /* Seek to the start of the core. */ 448 Lseek(ifd, (off_t)dumplo, L_SET); 449 450 if (kvm_dump_wrtheader(kd_dump, fp, dumpsize) == -1) { 451 syslog(LOG_ERR, "kvm_dump_wrtheader: %s : %s", path, 452 kvm_geterr(kd_dump)); 453 exit(1); 454 } 455 456 /* Copy the core file. */ 457 syslog(LOG_NOTICE, "writing %score to %s", 458 compress ? "compressed " : "", path); 459 for (; dumpsize > 0; dumpsize -= nr) { 460 (void)printf("%6dK\r", dumpsize / 1024); 461 (void)fflush(stdout); 462 nr = read(ifd, buf, MIN(dumpsize, sizeof(buf))); 463 if (nr <= 0) { 464 if (nr == 0) 465 syslog(LOG_WARNING, 466 "WARNING: EOF on dump device"); 467 else 468 syslog(LOG_ERR, "%s: %m", rawp); 469 goto err2; 470 } 471 nw = fwrite(buf, 1, nr, fp); 472 if (nw != nr) { 473 syslog(LOG_ERR, "%s: %s", 474 path, strerror(nw == 0 ? EIO : errno)); 475err2: syslog(LOG_WARNING, 476 "WARNING: core may be incomplete"); 477 (void)printf("\n"); 478 exit(1); 479 } 480 } 481 (void)close(ifd); 482 (void)fclose(fp); 483 484 /* Copy the kernel. */ 485 ifd = Open(kernel ? kernel : _PATH_UNIX, O_RDONLY); 486 (void)snprintf(path, sizeof(path), "%s/netbsd.%d%s", 487 dirname, bounds, compress ? ".Z" : ""); 488 if (compress) { 489 if ((fp = zopen(path, "w", 0)) == NULL) { 490 syslog(LOG_ERR, "%s: %s", path, strerror(errno)); 491 exit(1); 492 } 493 } else 494 ofd = Create(path, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH); 495 syslog(LOG_NOTICE, "writing %skernel to %s", 496 compress ? "compressed " : "", path); 497 while ((nr = read(ifd, buf, sizeof(buf))) > 0) { 498 if (compress) 499 nw = fwrite(buf, 1, nr, fp); 500 else 501 nw = write(ofd, buf, nr); 502 if (nw != nr) { 503 syslog(LOG_ERR, "%s: %s", 504 path, strerror(nw == 0 ? EIO : errno)); 505 syslog(LOG_WARNING, 506 "WARNING: kernel may be incomplete"); 507 exit(1); 508 } 509 } 510 if (nr < 0) { 511 syslog(LOG_ERR, "%s: %s", 512 kernel ? kernel : _PATH_UNIX, strerror(errno)); 513 syslog(LOG_WARNING, 514 "WARNING: kernel may be incomplete"); 515 exit(1); 516 } 517 if (compress) 518 (void)fclose(fp); 519 else 520 (void)close(ofd); 521} 522 523char * 524find_dev(dev, type) 525 register dev_t dev; 526 register int type; 527{ 528 register DIR *dfd; 529 struct dirent *dir; 530 struct stat sb; 531 char *dp, devname[MAXPATHLEN + 1]; 532 533 if ((dfd = opendir(_PATH_DEV)) == NULL) { 534 syslog(LOG_ERR, "%s: %s", _PATH_DEV, strerror(errno)); 535 exit(1); 536 } 537 (void)strcpy(devname, _PATH_DEV); 538 while ((dir = readdir(dfd))) { 539 (void)strcpy(devname + sizeof(_PATH_DEV) - 1, dir->d_name); 540 if (lstat(devname, &sb)) { 541 syslog(LOG_ERR, "%s: %s", devname, strerror(errno)); 542 continue; 543 } 544 if ((sb.st_mode & S_IFMT) != type) 545 continue; 546 if (dev == sb.st_rdev) { 547 closedir(dfd); 548 if ((dp = strdup(devname)) == NULL) { 549 syslog(LOG_ERR, "%s", strerror(errno)); 550 exit(1); 551 } 552 return (dp); 553 } 554 } 555 closedir(dfd); 556 syslog(LOG_ERR, "can't find device %d/%d", major(dev), minor(dev)); 557 exit(1); 558} 559 560char * 561rawname(s) 562 char *s; 563{ 564 char *sl, name[MAXPATHLEN]; 565 566 if ((sl = strrchr(s, '/')) == NULL || sl[1] == '0') { 567 syslog(LOG_ERR, 568 "can't make raw dump device name from %s", s); 569 return (s); 570 } 571 (void)snprintf(name, sizeof(name), "%.*s/r%s", sl - s, s, sl + 1); 572 if ((sl = strdup(name)) == NULL) { 573 syslog(LOG_ERR, "%s", strerror(errno)); 574 exit(1); 575 } 576 return (sl); 577} 578 579int 580get_crashtime() 581{ 582 time_t dumptime; /* Time the dump was taken. */ 583 584 if (KREAD(kd_dump, dump_nl[X_TIME].n_value, &dumptime) != 0) { 585 if (verbose) 586 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump)); 587 return (0); 588 } 589 if (dumptime == 0) { 590 if (verbose) 591 syslog(LOG_ERR, "dump time is zero"); 592 return (0); 593 } 594 (void)printf("savecore: system went down at %s", ctime(&dumptime)); 595#define LEEWAY (7 * SECSPERDAY) 596 if (dumptime < now - LEEWAY || dumptime > now + LEEWAY) { 597 (void)printf("dump time is unreasonable\n"); 598 return (0); 599 } 600 return (1); 601} 602 603int 604check_space() 605{ 606 register FILE *fp; 607 char *tkernel; 608 off_t minfree, spacefree, kernelsize, needed; 609 struct stat st; 610 struct statfs fsbuf; 611 char buf[100], path[MAXPATHLEN]; 612 613 tkernel = kernel ? kernel : _PATH_UNIX; 614 if (stat(tkernel, &st) < 0) { 615 syslog(LOG_ERR, "%s: %m", tkernel); 616 exit(1); 617 } 618 kernelsize = st.st_blocks * S_BLKSIZE; 619 if (statfs(dirname, &fsbuf) < 0) { 620 syslog(LOG_ERR, "%s: %m", dirname); 621 exit(1); 622 } 623 spacefree = (fsbuf.f_bavail * fsbuf.f_bsize) / 1024; 624 625 (void)snprintf(path, sizeof(path), "%s/minfree", dirname); 626 if ((fp = fopen(path, "r")) == NULL) 627 minfree = 0; 628 else { 629 if (fgets(buf, sizeof(buf), fp) == NULL) 630 minfree = 0; 631 else 632 minfree = atoi(buf); 633 (void)fclose(fp); 634 } 635 636 needed = (dumpsize + kernelsize) / 1024; 637 if (minfree > 0 && spacefree - needed < minfree) { 638 syslog(LOG_WARNING, 639 "no dump, not enough free space on device"); 640 return (0); 641 } 642 if (spacefree - needed < minfree) 643 syslog(LOG_WARNING, 644 "dump performed, but free space threshold crossed"); 645 return (1); 646} 647 648int 649Open(name, rw) 650 char *name; 651 int rw; 652{ 653 int fd; 654 655 if ((fd = open(name, rw, 0)) < 0) { 656 syslog(LOG_ERR, "%s: %m", name); 657 exit(1); 658 } 659 return (fd); 660} 661 662void 663Lseek(fd, off, flag) 664 int fd, flag; 665 off_t off; 666{ 667 off_t ret; 668 669 ret = lseek(fd, off, flag); 670 if (ret == -1) { 671 syslog(LOG_ERR, "lseek: %m"); 672 exit(1); 673 } 674} 675 676int 677Create(file, mode) 678 char *file; 679 int mode; 680{ 681 register int fd; 682 683 fd = open(file, O_WRONLY | O_CREAT | O_TRUNC, mode); 684 if (fd < 0) { 685 syslog(LOG_ERR, "%s: %m", file); 686 exit(1); 687 } 688 return (fd); 689} 690 691void 692Write(fd, bp, size) 693 int fd, size; 694 void *bp; 695{ 696 int n; 697 698 if ((n = write(fd, bp, size)) < size) { 699 syslog(LOG_ERR, "write: %s", strerror(n == -1 ? errno : EIO)); 700 exit(1); 701 } 702} 703 704void 705usage() 706{ 707 (void)syslog(LOG_ERR, "usage: savecore [-cfvz] [-N system] directory"); 708 exit(1); 709} 710