19b50d902SRodney W. Grimes /* 29b50d902SRodney W. Grimes * Copyright (c) 1980, 1987, 1992, 1993 39b50d902SRodney W. Grimes * The Regents of the University of California. All rights reserved. 49b50d902SRodney W. Grimes * 59b50d902SRodney W. Grimes * Redistribution and use in source and binary forms, with or without 69b50d902SRodney W. Grimes * modification, are permitted provided that the following conditions 79b50d902SRodney W. Grimes * are met: 89b50d902SRodney W. Grimes * 1. Redistributions of source code must retain the above copyright 99b50d902SRodney W. Grimes * notice, this list of conditions and the following disclaimer. 109b50d902SRodney W. Grimes * 2. Redistributions in binary form must reproduce the above copyright 119b50d902SRodney W. Grimes * notice, this list of conditions and the following disclaimer in the 129b50d902SRodney W. Grimes * documentation and/or other materials provided with the distribution. 139b50d902SRodney W. Grimes * 3. All advertising materials mentioning features or use of this software 149b50d902SRodney W. Grimes * must display the following acknowledgement: 159b50d902SRodney W. Grimes * This product includes software developed by the University of 169b50d902SRodney W. Grimes * California, Berkeley and its contributors. 179b50d902SRodney W. Grimes * 4. Neither the name of the University nor the names of its contributors 189b50d902SRodney W. Grimes * may be used to endorse or promote products derived from this software 199b50d902SRodney W. Grimes * without specific prior written permission. 209b50d902SRodney W. Grimes * 219b50d902SRodney W. Grimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 229b50d902SRodney W. Grimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 239b50d902SRodney W. Grimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 249b50d902SRodney W. Grimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 259b50d902SRodney W. Grimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 269b50d902SRodney W. Grimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 279b50d902SRodney W. Grimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 289b50d902SRodney W. Grimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 299b50d902SRodney W. Grimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 309b50d902SRodney W. Grimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 319b50d902SRodney W. Grimes * SUCH DAMAGE. 329b50d902SRodney W. Grimes */ 339b50d902SRodney W. Grimes 349b50d902SRodney W. Grimes #ifndef lint 35c8510085SPhilippe Charnier static const char copyright[] = 369b50d902SRodney W. Grimes "@(#) Copyright (c) 1980, 1987, 1992, 1993\n\ 379b50d902SRodney W. Grimes The Regents of the University of California. All rights reserved.\n"; 389b50d902SRodney W. Grimes #endif /* not lint */ 399b50d902SRodney W. Grimes 409b50d902SRodney W. Grimes #ifndef lint 41c8510085SPhilippe Charnier #if 0 42df3f5d9dSPeter Wemm static char sccsid[] = "@(#)head.c 8.2 (Berkeley) 5/4/95"; 43c8510085SPhilippe Charnier #endif 44c8510085SPhilippe Charnier static const char rcsid[] = 45c3aac50fSPeter Wemm "$FreeBSD$"; 469b50d902SRodney W. Grimes #endif /* not lint */ 479b50d902SRodney W. Grimes 489b50d902SRodney W. Grimes #include <sys/types.h> 49df3f5d9dSPeter Wemm 50df3f5d9dSPeter Wemm #include <ctype.h> 51c8510085SPhilippe Charnier #include <err.h> 52df3f5d9dSPeter Wemm #include <stdio.h> 539b50d902SRodney W. Grimes #include <stdlib.h> 549b50d902SRodney W. Grimes #include <string.h> 55df3f5d9dSPeter Wemm #include <unistd.h> 569b50d902SRodney W. Grimes 579b50d902SRodney W. Grimes /* 589b50d902SRodney W. Grimes * head - give the first few lines of a stream or of each of a set of files 599b50d902SRodney W. Grimes * 609b50d902SRodney W. Grimes * Bill Joy UCB August 24, 1977 619b50d902SRodney W. Grimes */ 629b50d902SRodney W. Grimes 639b50d902SRodney W. Grimes void head __P((FILE *, int)); 64ef0e2ea4SAlexander Langer void head_bytes __P((FILE *, int)); 659b50d902SRodney W. Grimes void obsolete __P((char *[])); 669b50d902SRodney W. Grimes void usage __P((void)); 679b50d902SRodney W. Grimes 689b50d902SRodney W. Grimes int 699b50d902SRodney W. Grimes main(argc, argv) 709b50d902SRodney W. Grimes int argc; 719b50d902SRodney W. Grimes char *argv[]; 729b50d902SRodney W. Grimes { 739b50d902SRodney W. Grimes register int ch; 749b50d902SRodney W. Grimes FILE *fp; 75c16b5e4fSAlfred Perlstein int first, linecnt = -1, bytecnt = -1, eval = 0; 769b50d902SRodney W. Grimes char *ep; 779b50d902SRodney W. Grimes 789b50d902SRodney W. Grimes obsolete(argv); 79ef0e2ea4SAlexander Langer while ((ch = getopt(argc, argv, "n:c:")) != -1) 809b50d902SRodney W. Grimes switch(ch) { 81ef0e2ea4SAlexander Langer case 'c': 82ef0e2ea4SAlexander Langer bytecnt = strtol(optarg, &ep, 10); 83ef0e2ea4SAlexander Langer if (*ep || bytecnt <= 0) 84c8510085SPhilippe Charnier errx(1, "illegal byte count -- %s", optarg); 85ef0e2ea4SAlexander Langer break; 869b50d902SRodney W. Grimes case 'n': 879b50d902SRodney W. Grimes linecnt = strtol(optarg, &ep, 10); 889b50d902SRodney W. Grimes if (*ep || linecnt <= 0) 89c8510085SPhilippe Charnier errx(1, "illegal line count -- %s", optarg); 909b50d902SRodney W. Grimes break; 919b50d902SRodney W. Grimes case '?': 929b50d902SRodney W. Grimes default: 939b50d902SRodney W. Grimes usage(); 949b50d902SRodney W. Grimes } 959b50d902SRodney W. Grimes argc -= optind; 969b50d902SRodney W. Grimes argv += optind; 979b50d902SRodney W. Grimes 98ef0e2ea4SAlexander Langer if (linecnt != -1 && bytecnt != -1) 99c8510085SPhilippe Charnier errx(1, "can't combine line and byte counts"); 100ef0e2ea4SAlexander Langer if (linecnt == -1 ) 101ef0e2ea4SAlexander Langer linecnt = 10; 102ef0e2ea4SAlexander Langer if (*argv) { 1039b50d902SRodney W. Grimes for (first = 1; *argv; ++argv) { 1049b50d902SRodney W. Grimes if ((fp = fopen(*argv, "r")) == NULL) { 105c8510085SPhilippe Charnier warn("%s", *argv); 10673f3d053SPhilippe Charnier eval = 1; 1079b50d902SRodney W. Grimes continue; 1089b50d902SRodney W. Grimes } 1099b50d902SRodney W. Grimes if (argc > 1) { 1109b50d902SRodney W. Grimes (void)printf("%s==> %s <==\n", 1119b50d902SRodney W. Grimes first ? "" : "\n", *argv); 1129b50d902SRodney W. Grimes first = 0; 1139b50d902SRodney W. Grimes } 114ef0e2ea4SAlexander Langer if (bytecnt == -1) 1159b50d902SRodney W. Grimes head(fp, linecnt); 116ef0e2ea4SAlexander Langer else 117ef0e2ea4SAlexander Langer head_bytes(fp, bytecnt); 1189b50d902SRodney W. Grimes (void)fclose(fp); 1199b50d902SRodney W. Grimes } 120c16b5e4fSAlfred Perlstein } else if (bytecnt == -1) 1219b50d902SRodney W. Grimes head(stdin, linecnt); 122ef0e2ea4SAlexander Langer else 123ef0e2ea4SAlexander Langer head_bytes(stdin, bytecnt); 124ef0e2ea4SAlexander Langer 1259b50d902SRodney W. Grimes exit(eval); 1269b50d902SRodney W. Grimes } 1279b50d902SRodney W. Grimes 1289b50d902SRodney W. Grimes void 1299b50d902SRodney W. Grimes head(fp, cnt) 1309b50d902SRodney W. Grimes FILE *fp; 1319b50d902SRodney W. Grimes register int cnt; 1329b50d902SRodney W. Grimes { 133c7a2aa5dSAlfred Perlstein char *cp; 134c7a2aa5dSAlfred Perlstein int error, readlen; 1359b50d902SRodney W. Grimes 136c7a2aa5dSAlfred Perlstein while (cnt && (cp = fgetln(fp, &readlen)) != NULL) { 137c7a2aa5dSAlfred Perlstein error = fwrite(cp, sizeof(char), readlen, stdout); 138c7a2aa5dSAlfred Perlstein if (error != readlen) 139c8510085SPhilippe Charnier err(1, "stdout"); 1408e502f11SJoerg Wunsch cnt--; 1419b50d902SRodney W. Grimes } 1429b50d902SRodney W. Grimes } 1439b50d902SRodney W. Grimes 1449b50d902SRodney W. Grimes void 145ef0e2ea4SAlexander Langer head_bytes(fp, cnt) 146ef0e2ea4SAlexander Langer FILE *fp; 147ef0e2ea4SAlexander Langer register int cnt; 148ef0e2ea4SAlexander Langer { 149ef0e2ea4SAlexander Langer char buf[4096]; 150ef0e2ea4SAlexander Langer register int readlen; 151ef0e2ea4SAlexander Langer 152ef0e2ea4SAlexander Langer while (cnt) { 153ef0e2ea4SAlexander Langer if (cnt < sizeof(buf)) 154ef0e2ea4SAlexander Langer readlen = cnt; 155ef0e2ea4SAlexander Langer else 156ef0e2ea4SAlexander Langer readlen = sizeof(buf); 157ef0e2ea4SAlexander Langer readlen = fread(buf, sizeof(char), readlen, fp); 158710668caSDag-Erling Smørgrav if (readlen == 0) 159ef0e2ea4SAlexander Langer break; 160ef0e2ea4SAlexander Langer if (fwrite(buf, sizeof(char), readlen, stdout) != readlen) 161c8510085SPhilippe Charnier err(1, "stdout"); 162ef0e2ea4SAlexander Langer cnt -= readlen; 163ef0e2ea4SAlexander Langer } 164ef0e2ea4SAlexander Langer } 165ef0e2ea4SAlexander Langer 166ef0e2ea4SAlexander Langer void 1679b50d902SRodney W. Grimes obsolete(argv) 1689b50d902SRodney W. Grimes char *argv[]; 1699b50d902SRodney W. Grimes { 1709b50d902SRodney W. Grimes char *ap; 1719b50d902SRodney W. Grimes 172ef0e2ea4SAlexander Langer while ((ap = *++argv)) { 1739b50d902SRodney W. Grimes /* Return if "--" or not "-[0-9]*". */ 1749b50d902SRodney W. Grimes if (ap[0] != '-' || ap[1] == '-' || !isdigit(ap[1])) 1759b50d902SRodney W. Grimes return; 1769b50d902SRodney W. Grimes if ((ap = malloc(strlen(*argv) + 2)) == NULL) 177c8510085SPhilippe Charnier err(1, NULL); 1789b50d902SRodney W. Grimes ap[0] = '-'; 1799b50d902SRodney W. Grimes ap[1] = 'n'; 1809b50d902SRodney W. Grimes (void)strcpy(ap + 2, *argv + 1); 1819b50d902SRodney W. Grimes *argv = ap; 1829b50d902SRodney W. Grimes } 1839b50d902SRodney W. Grimes } 1849b50d902SRodney W. Grimes 1859b50d902SRodney W. Grimes void 1869b50d902SRodney W. Grimes usage() 1879b50d902SRodney W. Grimes { 188c16b5e4fSAlfred Perlstein 189c8510085SPhilippe Charnier (void)fprintf(stderr, "usage: head [-n lines] [-c bytes] [file ...]\n"); 1909b50d902SRodney W. Grimes exit(1); 1919b50d902SRodney W. Grimes } 192