A very simple C program for inspecting binaries.

inspect.c

/*
	This program is free software: you can redistribute it and/or modify
	it under the terms of the GNU General Public License as published by
	the Free Software Foundation, either version 3 of the License, or
	(at your option) any later version.
	
	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	GNU General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdio.h>
#include <string.h>
#include <errno.h>

void inspect(FILE *file, unsigned width);

int main(int argc, const char **argv) {
	unsigned width = 1;
	char width_arg[] = "-w";
	const char *filename = NULL;
	{
		int i;
		for (i = 1; i < argc; i++) {
			if (strcmp(argv[i], width_arg) == 0) {
				i++;
				if (i >= argc) {
					fprintf(stderr, "Expecting one more argument after %s.\n", width_arg);
					return 1;
				}
				sscanf(argv[i], "%u\n", &width);
			} else {
				filename = argv[i];
			}
		}
	}
	if (filename == NULL) {
		inspect(stdin, width);
	} else {
		FILE *file = fopen(filename, "r");
		if (file == NULL) {
			fprintf(stderr, "Error opening %s: %s.\n", filename, strerror(errno));
			return 2;
		}
		inspect(file, width);
		fclose(file);
	}
	return 0;
}


void inspect(FILE *file, unsigned width) {
	int ch = fgetc(file);
	long long unsigned i = 0;
	while (ch != EOF) {
		char ch_str[2] = {ch, 0};
		char *toprint = NULL;
		switch (ch) {
			case '\n':
				toprint = "\\n";
				break;
			case '\b':
				toprint = "\\b";
				break;
			case '\r':
				toprint = "\\r";
				break;
			case '\0':
				toprint = "\\0";
				break;
			case '\f':
				toprint = "\\f";
				break;
			case '\v':
				toprint = "\\v";
				break;
			case '\t':
				toprint = "\\t";
				break;
			case 27:
				toprint = "\\ESC";
				break;
			case 127:
				toprint = "\\DEL";
				break;
			default:
				toprint = ch_str;
				break;
		}
		printf("[%llu]: %u (%s)", i, ch, toprint);
		ch = fgetc(file);
		if ((i + 1) % width == 0 || ch == EOF) fputc('\n', stdout);
		else fputs(" | ", stdout);
		i++;
	}

}