48 lines
914 B
C
48 lines
914 B
C
/* See LICENSE file for copyright and license details. */
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#include <stdio.h>
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#include <stdlib.h>
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#include <unistd.h>
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#include "util.h"
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static void head(FILE *, const char *, long);
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int
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main(int argc, char *argv[])
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{
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char *end, c;
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long n = 10;
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FILE *fp;
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while((c = getopt(argc, argv, "n:")) != -1)
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switch(c) {
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case 'n':
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n = strtol(optarg, &end, 0);
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if(*end != '\0')
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eprintf("%s: not a number\n", optarg);
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break;
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default:
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exit(EXIT_FAILURE);
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}
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if(optind == argc)
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head(stdin, "<stdin>", n);
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else for(; optind < argc; optind++) {
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if(!(fp = fopen(argv[optind], "r")))
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eprintf("fopen %s:", argv[optind]);
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head(fp, argv[optind], n);
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fclose(fp);
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}
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return EXIT_SUCCESS;
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}
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void
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head(FILE *fp, const char *str, long n)
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{
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char buf[BUFSIZ];
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int i;
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for(i = 0; i < n && fgets(buf, sizeof buf, fp); i++)
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fputs(buf, stdout);
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if(ferror(fp))
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eprintf("%s: read error:", str);
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}
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