Commit | Line | Data |
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22e155fc | 1 | /* |
c482e60f | 2 | * Copyright (c) 1980, 1987 Regents of the University of California. |
33e97575 KB |
3 | * All rights reserved. |
4 | * | |
f15db449 | 5 | * %sccs.include.redist.c% |
22e155fc DF |
6 | */ |
7 | ||
8 | #ifndef lint | |
9 | char copyright[] = | |
c482e60f | 10 | "@(#) Copyright (c) 1980, 1987 Regents of the University of California.\n\ |
22e155fc | 11 | All rights reserved.\n"; |
33e97575 | 12 | #endif /* not lint */ |
22e155fc DF |
13 | |
14 | #ifndef lint | |
f15db449 | 15 | static char sccsid[] = "@(#)head.c 5.5 (Berkeley) %G%"; |
33e97575 | 16 | #endif /* not lint */ |
22e155fc | 17 | |
9c87fed6 | 18 | #include <stdio.h> |
c482e60f | 19 | #include <ctype.h> |
9c87fed6 BJ |
20 | /* |
21 | * head - give the first few lines of a stream or of each of a set of files | |
22 | * | |
23 | * Bill Joy UCB August 24, 1977 | |
24 | */ | |
25 | ||
c482e60f KB |
26 | main(argc, argv) |
27 | int argc; | |
28 | char **argv; | |
9c87fed6 | 29 | { |
c482e60f KB |
30 | register int ch, cnt; |
31 | int firsttime, linecnt = 10; | |
9c87fed6 | 32 | |
c482e60f KB |
33 | if (argc > 1 && argv[1][0] == '-') { |
34 | if (!isdigit(argv[1][1])) { | |
35 | fprintf(stderr, "head: illegal option -- %c\n", argv[1][1]); | |
36 | goto usage; | |
37 | } | |
38 | if ((linecnt = atoi(argv[1] + 1)) < 0) { | |
39 | usage: fputs("usage: head [-line_count] [file ...]\n", stderr); | |
40 | exit(1); | |
41 | } | |
42 | --argc; ++argv; | |
43 | } | |
44 | /* setlinebuf(stdout); */ | |
45 | for (firsttime = 1, --argc, ++argv;; firsttime = 0) { | |
46 | if (!*argv) { | |
47 | if (!firsttime) | |
48 | exit(0); | |
9c87fed6 | 49 | } |
c482e60f KB |
50 | else { |
51 | if (!freopen(*argv, "r", stdin)) { | |
52 | fprintf(stderr, "head: can't read %s.\n", *argv); | |
9c87fed6 BJ |
53 | exit(1); |
54 | } | |
c482e60f KB |
55 | if (argc > 1) { |
56 | if (!firsttime) | |
57 | putchar('\n'); | |
58 | printf("==> %s <==\n", *argv); | |
59 | } | |
60 | ++argv; | |
61 | } | |
62 | for (cnt = linecnt; cnt; --cnt) | |
63 | while ((ch = getchar()) != EOF) | |
64 | if (putchar(ch) == '\n') | |
65 | break; | |
9c87fed6 | 66 | } |
c482e60f | 67 | /*NOTREACHED*/ |
9c87fed6 | 68 | } |