savecore.c revision 1.32
1/* $NetBSD: savecore.c,v 1.32 1997/09/15 11:08:45 lukem 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#include <sys/cdefs.h> 37#ifndef lint 38__COPYRIGHT("@(#) 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 46__RCSID("$NetBSD: savecore.c,v 1.32 1997/09/15 11:08:45 lukem 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 main __P((int, char *[])); 134int Open __P((char *, int rw)); 135char *rawname __P((char *s)); 136void save_core __P((void)); 137void usage __P((void)); 138void Write __P((int, void *, int)); 139 140int 141main(argc, argv) 142 int argc; 143 char *argv[]; 144{ 145 int ch; 146 147 openlog("savecore", LOG_PERROR, LOG_DAEMON); 148 149 while ((ch = getopt(argc, argv, "cdfN:vz")) != -1) 150 switch(ch) { 151 case 'c': 152 clear = 1; 153 break; 154 case 'd': /* Not documented. */ 155 case 'v': 156 verbose = 1; 157 break; 158 case 'f': 159 force = 1; 160 break; 161 case 'N': 162 kernel = optarg; 163 break; 164 case 'z': 165 compress = 1; 166 break; 167 case '?': 168 default: 169 usage(); 170 } 171 argc -= optind; 172 argv += optind; 173 174 if (!clear) { 175 if (argc != 1 && argc != 2) 176 usage(); 177 dirname = argv[0]; 178 } 179 if (argc == 2) 180 kernel = argv[1]; 181 182 (void)time(&now); 183 kmem_setup(); 184 185 if (clear) { 186 clear_dump(); 187 exit(0); 188 } 189 190 if (!dump_exists() && !force) 191 exit(1); 192 193 check_kmem(); 194 195 if (panicstr) 196 syslog(LOG_ALERT, "reboot after panic: %s", panic_mesg); 197 else 198 syslog(LOG_ALERT, "reboot"); 199 200 if ((!get_crashtime() || !check_space()) && !force) 201 exit(1); 202 203 save_core(); 204 205 clear_dump(); 206 exit(0); 207} 208 209void 210kmem_setup() 211{ 212 kvm_t *kd_kern; 213 char errbuf[_POSIX2_LINE_MAX]; 214 int i, hdrsz; 215 char *dump_sys; 216 217 /* 218 * Some names we need for the currently running system, others for 219 * the system that was running when the dump was made. The values 220 * obtained from the current system are used to look for things in 221 * /dev/kmem that cannot be found in the dump_sys namelist, but are 222 * presumed to be the same (since the disk partitions are probably 223 * the same!) 224 */ 225 kd_kern = kvm_openfiles(NULL, NULL, NULL, O_RDONLY, errbuf); 226 if (kd_kern == NULL) { 227 syslog(LOG_ERR, "%s: kvm_openfiles: %s", _PATH_UNIX, errbuf); 228 exit(1); 229 } 230 if (kvm_nlist(kd_kern, current_nl) == -1) 231 syslog(LOG_ERR, "%s: kvm_nlist: %s", _PATH_UNIX, 232 kvm_geterr(kd_kern)); 233 234 for (i = 0; cursyms[i] != -1; i++) 235 if (current_nl[cursyms[i]].n_value == 0) { 236 syslog(LOG_ERR, "%s: %s not in namelist", 237 _PATH_UNIX, current_nl[cursyms[i]].n_name); 238 exit(1); 239 } 240 241 if (KREAD(kd_kern, current_nl[X_DUMPDEV].n_value, &dumpdev) != 0) { 242 if (verbose) 243 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_kern)); 244 exit(1); 245 } 246 if (dumpdev == NODEV) { 247 syslog(LOG_WARNING, "no core dump (no dumpdev)"); 248 exit(1); 249 } 250 if (KREAD(kd_kern, current_nl[X_DUMPLO].n_value, &dumplo) != 0) { 251 if (verbose) 252 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_kern)); 253 exit(1); 254 } 255 dumplo *= DEV_BSIZE; 256 if (verbose) 257 (void)printf("dumplo = %ld (%ld * %ld)\n", 258 (long)dumplo, (long)(dumplo / DEV_BSIZE), (long)DEV_BSIZE); 259 if (KREAD(kd_kern, current_nl[X_DUMPMAG].n_value, &dumpmag) != 0) { 260 if (verbose) 261 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_kern)); 262 exit(1); 263 } 264 265 if (kernel == NULL) { 266 (void)kvm_read(kd_kern, current_nl[X_VERSION].n_value, 267 vers, sizeof(vers)); 268 vers[sizeof(vers) - 1] = '\0'; 269 } 270 271 ddname = find_dev(dumpdev, S_IFBLK); 272 dumpfd = Open(ddname, O_RDWR); 273 274 dump_sys = kernel ? kernel : _PATH_UNIX; 275 276 kd_dump = kvm_openfiles(dump_sys, ddname, NULL, O_RDWR, errbuf); 277 if (kd_dump == NULL) { 278 syslog(LOG_ERR, "%s: kvm_openfiles: %s", dump_sys, errbuf); 279 exit(1); 280 } 281 282 if (kvm_nlist(kd_dump, dump_nl) == -1) 283 syslog(LOG_ERR, "%s: kvm_nlist: %s", dump_sys, 284 kvm_geterr(kd_dump)); 285 286 for (i = 0; dumpsyms[i] != -1; i++) 287 if (dump_nl[dumpsyms[i]].n_value == 0) { 288 syslog(LOG_ERR, "%s: %s not in namelist", 289 dump_sys, dump_nl[dumpsyms[i]].n_name); 290 exit(1); 291 } 292 hdrsz = kvm_dump_mkheader(kd_dump, (off_t)dumplo); 293 294 /* 295 * If 'hdrsz' == 0, kvm_dump_mkheader() failed on the magic-number 296 * checks, ergo no dump is present... 297 */ 298 if (hdrsz == 0) { 299 syslog(LOG_WARNING, "no core dump"); 300 exit(1); 301 } 302 if (hdrsz == -1) { 303 syslog(LOG_ERR, "%s: kvm_dump_mkheader: %s", dump_sys, 304 kvm_geterr(kd_dump)); 305 exit(1); 306 } 307 dumplo += hdrsz; 308 kvm_close(kd_kern); 309} 310 311void 312check_kmem() 313{ 314 char *cp; 315 long panicloc; 316 char core_vers[1024]; 317 318 (void)kvm_read(kd_dump, dump_nl[X_VERSION].n_value, core_vers, 319 sizeof(core_vers)); 320 core_vers[sizeof(core_vers) - 1] = '\0'; 321 322 if (strcmp(vers, core_vers) && kernel == 0) 323 syslog(LOG_WARNING, 324 "warning: %s version mismatch:\n\t%s\nand\t%s\n", 325 _PATH_UNIX, vers, core_vers); 326 327 if (KREAD(kd_dump, dump_nl[X_PANICSTR].n_value, &panicstr) != 0) { 328 if (verbose) 329 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump)); 330 return; 331 } 332 if (panicstr) { 333 cp = panic_mesg; 334 panicloc = panicstr; 335 do { 336 if (KREAD(kd_dump, panicloc, cp) != 0) { 337 if (verbose) 338 syslog(LOG_WARNING, "kvm_read: %s", 339 kvm_geterr(kd_dump)); 340 break; 341 } 342 panicloc++; 343 } while (*cp++ && cp < &panic_mesg[sizeof(panic_mesg)-1]); 344 panic_mesg[sizeof(panic_mesg) - 1] = '\0'; 345 } 346} 347 348int 349dump_exists() 350{ 351 int newdumpmag; 352 353 if (KREAD(kd_dump, dump_nl[X_DUMPMAG].n_value, &newdumpmag) != 0) { 354 if (verbose) 355 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump)); 356 return (0); 357 } 358 359 /* Read the dump size. */ 360 if (KREAD(kd_dump, dump_nl[X_DUMPSIZE].n_value, &dumpsize) != 0) { 361 if (verbose) 362 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump)); 363 return (0); 364 } 365 dumpsize *= getpagesize(); 366 367 /* 368 * Return zero if core dump doesn't seem to be there, and note 369 * it for syslog. This check and return happens after the dump size 370 * is read, so dumpsize is whether or not the core is valid (for -f). 371 */ 372 if (newdumpmag != dumpmag) { 373 if (verbose) 374 syslog(LOG_WARNING, 375 "magic number mismatch (0x%x != 0x%x)", 376 newdumpmag, dumpmag); 377 syslog(LOG_WARNING, "no core dump"); 378 return (0); 379 } 380 return (1); 381} 382 383void 384clear_dump() 385{ 386 if (kvm_dump_inval(kd_dump) == -1) 387 syslog(LOG_ERR, "%s: kvm_clear_dump: %s", ddname, 388 kvm_geterr(kd_dump)); 389 390} 391 392char buf[1024 * 1024]; 393 394void 395save_core() 396{ 397 FILE *fp; 398 int bounds, ifd, nr, nw, ofd; 399 char *rawp, path[MAXPATHLEN]; 400 401 ofd = -1; 402 /* 403 * Get the current number and update the bounds file. Do the update 404 * now, because may fail later and don't want to overwrite anything. 405 */ 406 umask(002); 407 (void)snprintf(path, sizeof(path), "%s/bounds", dirname); 408 if ((fp = fopen(path, "r")) == NULL) 409 goto err1; 410 if (fgets(buf, sizeof(buf), fp) == NULL) { 411 if (ferror(fp)) 412err1: syslog(LOG_WARNING, "%s: %s", path, strerror(errno)); 413 bounds = 0; 414 } else 415 bounds = atoi(buf); 416 if (fp != NULL) 417 (void)fclose(fp); 418 if ((fp = fopen(path, "w")) == NULL) 419 syslog(LOG_ERR, "%s: %m", path); 420 else { 421 (void)fprintf(fp, "%d\n", bounds + 1); 422 (void)fclose(fp); 423 } 424 (void)fclose(fp); 425 426 /* Create the core file. */ 427 (void)snprintf(path, sizeof(path), "%s/netbsd.%d.core%s", 428 dirname, bounds, compress ? ".Z" : ""); 429 if (compress) { 430 if ((fp = zopen(path, "w", 0)) == NULL) { 431 syslog(LOG_ERR, "%s: %s", path, strerror(errno)); 432 exit(1); 433 } 434 } else { 435 ofd = Create(path, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH); 436 fp = fdopen(ofd, "w"); 437 if (fp == NULL) { 438 syslog(LOG_ERR, "%s: fdopen: %s", path, 439 strerror(errno)); 440 exit(1); 441 } 442 } 443 444 /* Open the raw device. */ 445 rawp = rawname(ddname); 446 if ((ifd = open(rawp, O_RDONLY)) == -1) { 447 syslog(LOG_WARNING, "%s: %m; using block device", rawp); 448 ifd = dumpfd; 449 } 450 451 /* Seek to the start of the core. */ 452 Lseek(ifd, (off_t)dumplo, SEEK_SET); 453 454 if (kvm_dump_wrtheader(kd_dump, fp, dumpsize) == -1) { 455 syslog(LOG_ERR, "kvm_dump_wrtheader: %s : %s", path, 456 kvm_geterr(kd_dump)); 457 exit(1); 458 } 459 460 /* Copy the core file. */ 461 syslog(LOG_NOTICE, "writing %score to %s", 462 compress ? "compressed " : "", path); 463 for (; dumpsize > 0; dumpsize -= nr) { 464 (void)printf("%6dK\r", dumpsize / 1024); 465 (void)fflush(stdout); 466 nr = read(ifd, buf, MIN(dumpsize, sizeof(buf))); 467 if (nr <= 0) { 468 if (nr == 0) 469 syslog(LOG_WARNING, 470 "WARNING: EOF on dump device"); 471 else 472 syslog(LOG_ERR, "%s: %m", rawp); 473 goto err2; 474 } 475 nw = fwrite(buf, 1, nr, fp); 476 if (nw != nr) { 477 syslog(LOG_ERR, "%s: %s", 478 path, strerror(nw == 0 ? EIO : errno)); 479err2: syslog(LOG_WARNING, 480 "WARNING: core may be incomplete"); 481 (void)printf("\n"); 482 exit(1); 483 } 484 } 485 (void)close(ifd); 486 (void)fclose(fp); 487 488 /* Copy the kernel. */ 489 ifd = Open(kernel ? kernel : _PATH_UNIX, O_RDONLY); 490 (void)snprintf(path, sizeof(path), "%s/netbsd.%d%s", 491 dirname, bounds, compress ? ".Z" : ""); 492 if (compress) { 493 if ((fp = zopen(path, "w", 0)) == NULL) { 494 syslog(LOG_ERR, "%s: %s", path, strerror(errno)); 495 exit(1); 496 } 497 } else 498 ofd = Create(path, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH); 499 syslog(LOG_NOTICE, "writing %skernel to %s", 500 compress ? "compressed " : "", path); 501 while ((nr = read(ifd, buf, sizeof(buf))) > 0) { 502 if (compress) 503 nw = fwrite(buf, 1, nr, fp); 504 else 505 nw = write(ofd, buf, nr); 506 if (nw != nr) { 507 syslog(LOG_ERR, "%s: %s", 508 path, strerror(nw == 0 ? EIO : errno)); 509 syslog(LOG_WARNING, 510 "WARNING: kernel may be incomplete"); 511 exit(1); 512 } 513 } 514 if (nr < 0) { 515 syslog(LOG_ERR, "%s: %s", 516 kernel ? kernel : _PATH_UNIX, strerror(errno)); 517 syslog(LOG_WARNING, 518 "WARNING: kernel may be incomplete"); 519 exit(1); 520 } 521 if (compress) 522 (void)fclose(fp); 523 else 524 (void)close(ofd); 525} 526 527char * 528find_dev(dev, type) 529 dev_t dev; 530 int type; 531{ 532 DIR *dfd; 533 struct dirent *dir; 534 struct stat sb; 535 char *dp, devname[MAXPATHLEN + 1]; 536 537 if ((dfd = opendir(_PATH_DEV)) == NULL) { 538 syslog(LOG_ERR, "%s: %s", _PATH_DEV, strerror(errno)); 539 exit(1); 540 } 541 (void)strcpy(devname, _PATH_DEV); 542 while ((dir = readdir(dfd))) { 543 (void)strcpy(devname + sizeof(_PATH_DEV) - 1, dir->d_name); 544 if (lstat(devname, &sb)) { 545 syslog(LOG_ERR, "%s: %s", devname, strerror(errno)); 546 continue; 547 } 548 if ((sb.st_mode & S_IFMT) != type) 549 continue; 550 if (dev == sb.st_rdev) { 551 closedir(dfd); 552 if ((dp = strdup(devname)) == NULL) { 553 syslog(LOG_ERR, "%s", strerror(errno)); 554 exit(1); 555 } 556 return (dp); 557 } 558 } 559 closedir(dfd); 560 syslog(LOG_ERR, "can't find device %d/%d", major(dev), minor(dev)); 561 exit(1); 562} 563 564char * 565rawname(s) 566 char *s; 567{ 568 char *sl, name[MAXPATHLEN]; 569 570 if ((sl = strrchr(s, '/')) == NULL || sl[1] == '0') { 571 syslog(LOG_ERR, 572 "can't make raw dump device name from %s", s); 573 return (s); 574 } 575 (void)snprintf(name, sizeof(name), "%.*s/r%s", sl - s, s, sl + 1); 576 if ((sl = strdup(name)) == NULL) { 577 syslog(LOG_ERR, "%s", strerror(errno)); 578 exit(1); 579 } 580 return (sl); 581} 582 583int 584get_crashtime() 585{ 586 time_t dumptime; /* Time the dump was taken. */ 587 588 if (KREAD(kd_dump, dump_nl[X_TIME].n_value, &dumptime) != 0) { 589 if (verbose) 590 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump)); 591 return (0); 592 } 593 if (dumptime == 0) { 594 if (verbose) 595 syslog(LOG_ERR, "dump time is zero"); 596 return (0); 597 } 598 (void)printf("savecore: system went down at %s", ctime(&dumptime)); 599#define LEEWAY (7 * SECSPERDAY) 600 if (dumptime < now - LEEWAY || dumptime > now + LEEWAY) { 601 (void)printf("dump time is unreasonable\n"); 602 return (0); 603 } 604 return (1); 605} 606 607int 608check_space() 609{ 610 FILE *fp; 611 char *tkernel; 612 off_t minfree, spacefree, kernelsize, needed; 613 struct stat st; 614 struct statfs fsbuf; 615 char buf[100], path[MAXPATHLEN]; 616 617 tkernel = kernel ? kernel : _PATH_UNIX; 618 if (stat(tkernel, &st) < 0) { 619 syslog(LOG_ERR, "%s: %m", tkernel); 620 exit(1); 621 } 622 kernelsize = st.st_blocks * S_BLKSIZE; 623 if (statfs(dirname, &fsbuf) < 0) { 624 syslog(LOG_ERR, "%s: %m", dirname); 625 exit(1); 626 } 627 spacefree = (fsbuf.f_bavail * fsbuf.f_bsize) / 1024; 628 629 (void)snprintf(path, sizeof(path), "%s/minfree", dirname); 630 if ((fp = fopen(path, "r")) == NULL) 631 minfree = 0; 632 else { 633 if (fgets(buf, sizeof(buf), fp) == NULL) 634 minfree = 0; 635 else 636 minfree = atoi(buf); 637 (void)fclose(fp); 638 } 639 640 needed = (dumpsize + kernelsize) / 1024; 641 if (minfree > 0 && spacefree - needed < minfree) { 642 syslog(LOG_WARNING, 643 "no dump, not enough free space on device"); 644 return (0); 645 } 646 if (spacefree - needed < minfree) 647 syslog(LOG_WARNING, 648 "dump performed, but free space threshold crossed"); 649 return (1); 650} 651 652int 653Open(name, rw) 654 char *name; 655 int rw; 656{ 657 int fd; 658 659 if ((fd = open(name, rw, 0)) < 0) { 660 syslog(LOG_ERR, "%s: %m", name); 661 exit(1); 662 } 663 return (fd); 664} 665 666void 667Lseek(fd, off, flag) 668 int fd, flag; 669 off_t off; 670{ 671 off_t ret; 672 673 ret = lseek(fd, off, flag); 674 if (ret == -1) { 675 syslog(LOG_ERR, "lseek: %m"); 676 exit(1); 677 } 678} 679 680int 681Create(file, mode) 682 char *file; 683 int mode; 684{ 685 int fd; 686 687 fd = open(file, O_WRONLY | O_CREAT | O_TRUNC, mode); 688 if (fd < 0) { 689 syslog(LOG_ERR, "%s: %m", file); 690 exit(1); 691 } 692 return (fd); 693} 694 695void 696Write(fd, bp, size) 697 int fd, size; 698 void *bp; 699{ 700 int n; 701 702 if ((n = write(fd, bp, size)) < size) { 703 syslog(LOG_ERR, "write: %s", strerror(n == -1 ? errno : EIO)); 704 exit(1); 705 } 706} 707 708void 709usage() 710{ 711 (void)syslog(LOG_ERR, "usage: savecore [-cfvz] [-N system] directory"); 712 exit(1); 713} 714