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/* SPDX-License-Identifier: BSD-3-Clause */
#include <fcntl.h>
#include <unistd.h>
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
#define REQ_PRINT_USAGE /* Require print_usage() from ../common/common.h */
#define REQ_ERRPRINT /* Require errprint() from ../common/common.h */
#define DESCRIPTION "Copy file to standard output until <number> lines."
#define OPERANDS "[-n number] [file] ..."
#include "../common/common.h"
int main(int argc, char *const argv[]) {
int argument, i, lines = 10, lines_printed;
FILE *file;
char s[4096], *argv0 = strdup(argv[0]);
while ((argument = getopt(argc, argv, "n:")) != -1) {
if (argument == '?' || argument == ':') {
print_usage(argv[0], DESCRIPTION, OPERANDS, VERSION);
return 1;
}
else if (argument == 'n') {
lines = strtol(optarg, NULL, 10);
if (errno) return errprint(argv[0], "strtol()", errno);
}
else
lines = 10;
} argc -= optind; argv += optind;
for (i = 0; i != argc || argc == 0; i++) {
if (argc == 0 || !strcmp(argv[i], "-"))
file = stdin;
else file = fopen(argv[i], "r");
if (file == NULL)
return errprint(argv0, argv[i], errno); /* Something went wrong */
for (lines_printed = 1; lines_printed <= lines; lines_printed++) {
if (fgets(s, 4096, file) != NULL)
printf("%s", s);
else return errprint(argv0, "fgets()", errno);
}
if (file != stdin) fclose(file);
if (argc == 0) return 0; /* TODO: Remove this stupid hack. */
}
return errprint(argv0, NULL, errno);
}
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