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/* head - copy the first part of files
* Copyright (C) 2022 Ferass EL HAFIDI
* Copyright (C) 2022 Leah Rowe
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the copyright holder nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <fcntl.h>
#include <unistd.h>
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
#include "version.h"
#ifndef COMPILETIME
#define COMPILETIME
#endif
/* Functions Prototypes */
int getopt(int argc, char *const argv[], const char *optstring);
void printUsage();
int main(int argc, char *const argv[]) {
int argument, i = 1, lines, lines_printed;
FILE *file;
char s[4096];
while ((argument = getopt(argc, argv, "n:")) != -1) {
if (argument == '?' || argument == ':') {
printUsage();
return 1;
}
else if (argument == 'n') {
lines = strtol(optarg, NULL, 10);
if (errno) return errno;
}
else
lines = 10;
}
if (argc < 2) {
while (read(STDIN_FILENO, s, 4096) > 0)
printf("%s", s);
}
if (!lines) lines = 10;
for (i = 1; i != argc; i++) {
if (strcmp(argv[i], "-n")) {
if (strcmp(argv[i], "-")) file = fopen(argv[i], "r");
else while (read(STDIN_FILENO, s, 4096) > 0) printf("%s", s);
if (file == NULL) return errno; /* Something went wrong */
for (lines_printed = 1; lines_printed <= lines; lines_printed++) {
if (fgets(s, 4096, file) != NULL)
printf("%s", s);
else if (errno) return errno;
}
fclose(file);
}
else i++;
}
return 0;
}
void printUsage() {
printf("Ferass' Base System. (%s)\n\n"
"Usage: head [-n number] [file]\n\n"
"Copy file to standard output until <number> lines.\n\n"
"\t-n number\tNumber of lines to be copied to standard output\n",
COMPILETIME);
}
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