Files
MentOS/programs/cat.c
T
Enrico Fraccaroli (Galfurian) 1b2bc49d41 Update license and remove unused files.
2022-01-27 15:12:36 -05:00

62 lines
1.7 KiB
C

/// @file cat.c
/// @brief `cat` program.
/// @copyright (c) 2014-2022 This file is distributed under the MIT License.
/// See LICENSE.md for details.
#include <fcntl.h>
#include <stdio.h>
#include <string.h>
#include <sys/unistd.h>
#include <strerror.h>
#include <sys/stat.h>
int main(int argc, char **argv)
{
if (argc < 2) {
printf("cat: missing operand.\n");
printf("Try 'cat --help' for more information.\n\n");
return 1;
}
// Check if `--help` is provided.
for (int i = 1; i < argc; ++i) {
if (strcmp(argv[i], "--help") == 0) {
printf("Prints the content of the given file.\n");
printf("Usage:\n");
printf(" cat <file>\n\n");
return 0;
}
}
// Prepare the buffer for reading.
char buffer[BUFSIZ];
// Iterate the arguments.
for (int i = 1; i < argc; ++i) {
int fd = open(argv[i], O_RDONLY, 42);
if (fd < 0) {
printf("cat: %s: %s\n\n", argv[i], strerror(errno));
continue;
}
stat_t statbuf;
if (fstat(fd, &statbuf) == -1) {
printf("cat: %s: %s\n\n", argv[i], strerror(errno));
// Close the file descriptor.
close(fd);
continue;
}
if (S_ISDIR(statbuf.st_mode)) {
printf("cat: %s: %s\n\n", argv[i], strerror(EISDIR));
// Close the file descriptor.
close(fd);
continue;
}
// Put on the standard output the characters.
while (read(fd, buffer, BUFSIZ) > 0) {
puts(buffer);
}
// Close the file descriptor.
close(fd);
}
putchar('\n');
putchar('\n');
return 0;
}