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/*
* UNG's Not GNU
*
* Copyright (c) 2011-2017, Jakob Kaivo <jkk@ung.org>
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
*/
#define _XOPEN_SOURCE 700
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
static int head(const char *path, int nlines)
{
FILE *f = stdin;
if (path && strcmp(path, "-")) {
f = fopen(path, "rb");
}
if (f == NULL) {
fprintf(stderr, "FIXME: Couldn't open %s: %s\n", path ? path : "stdin", strerror(errno));
return 1;
}
while (!feof(f) && nlines > 0) {
char *line = NULL;
size_t n = 0;
getline(&line, &n, f);
fputs(line, stdout);
nlines--;
}
if (f != stdin) {
fclose(f);
}
return 0;
}
int main(int argc, char **argv)
{
int lines = 10;
int showname = 0;
char *end;
int c;
while ((c = getopt(argc, argv, ":n:")) != -1) {
switch (c) {
case 'n':
lines = strtol(optarg, &end, 10);
if (end != NULL && strlen(end) > 0) {
fprintf(stderr, "head: Invalid number %s\n", optarg);
return 1;
}
break;
default:
return 1;
}
}
if (optind < argc - 1) {
showname = 1;
}
int r = 0;
do {
if (showname) {
if (showname == 1) {
showname++;
} else {
putchar('\n');
}
printf("==> %s <==\n", argv[optind]);
}
r |= head(argv[optind++], lines);
} while (optind < argc);
return r;
}
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