This is a review of Dan Gookin's book Tiny C Projects. I was made aware of the book by a fellow who is active in a Facebook group I run called not just Tiny C Programming Group. My friend noted the similarity between the book's name and the group's name but eventually realized Gookin's Tiny C and my Tiny C were different. His Tiny C is describing the size of the projects covered in the book, my Tiny C describes the size of a dialect of a C-like language.

C has spawned hundreds of languages which are often written in C. The Tiny C programming language was written in 8080 assembler in 1977 by Tom Gibson because he wanted to have a C-like language on his microprocessor-based computer. I bought it and typed in the source code from the users manual. Tiny C is a learning language, is simpler than C, and is a stepping stone to C. Later, Gibson implemented his language in C. Tiny C programs can be fairly easily translated into C. They can "call" C programs. I will talk about an example of this shortly.

Tiny C Projects is published by Manning Publications, Co. They have something they call MEAP (Manning Early Access Program). They also support an online "liveBook." It was through these two things that I got involved. In addition, Gookin maintains a GitHub repository for his book and proposed solutions to the projects may be downloaded from it.

The book was developed incrementally under MEAP and when I bought it, only the first five chapters or so were finished. Waiting for the next ones to come out was exciting.

The author tells you up front that you need to know the basics of C to follow the projects. I have been learning C for quite a while and have learned a lot more while doing his projects.

His book and my group are learn-by-doing undertakings. The first few chapters teach you how you can get your computer to run a program at startup and how you can cipher text by shifting the letters up or down the alphabet.

~$ echo "Can you read this?" | ./caesar01
Pna lbh ernq guvf?

The early chapters taught me how to modify a file called .bash_profile on my Dell desktop running Window Subsystem for Linux. I use a server to publish the solutions to exercises discussed in my Facebook group and the .bash_profile for my account on it currently contains:

./greet05 $LOGNAME
./pithy05
alias rot13="tr 'A-Za-z' 'N-ZA-Mn-za-m'"
cd public_html/not.just.tiny.c/

Gookin has been publishing computer books for a long time. He was weaned on the old PCs and fondly remembers the days of command line programming. He is comfortable with Linux and Windows and explains just enough to help you navigate if you are at a DOS terminal or a Linux terminal. He also has an incredible sense of humor. How many computer books have you read that make you laugh out loud?

His projects are fun, interesting and unlike anything you have seen before. The above is the Linux counterpart to a DOS AUTOEXEC.BAT. Commands here start with ./ (find the executable by looking in the current directory). pithy05 is the fifth version of a "fortune" program he develops. Here's what it might display:

Do I take a break from work to play a video game, or take a break from a
video game to get work done?

Greetings!
Today is Friday, February 03, 2023
It is 07:15:06 PM
The moon is full

Chapters 5 and 6 involve encoding and decoding text and password generation. One of the key things the author encourages you to do is take his example programs and extend them to support a new feature.

For example, after showing you how to encode the string

Hello, World!

into hex pairs

48 65 6C 6C 6F 2C 20 57 6F 72 6C 64 21

In his password chapter a function called scramble is discussed and you are asked to incorporate its use to make better passwords. I made a program I was working on better by modifying his scramble function to fit my needs.

scramble.2.10.23.c

secondchance.2.11.23.2.tc

leeunix@Lee:~$ ./tc secondchance.2.11.23.2.tc -r mainl
***  TINY-C VERSION 1.0,  COPYRIGHT 1977, T A GIBSON  ***
        This C version copyright 2017, T A Gibson

secondchance.tc - lrb - 2/11/23

How many simulations do you want (e.g. 100) : 20

 1* 2. 3. 4. 5* 6* 7. 8. 9. 10. 11. 12. 13* 14. 15. 16. 17. 18* 19. 20*

inmates saved : 6 inmates died : 14

If you're reading this review on a computer and clicked the link above to the C program, don't feel bad if you are lost trying to understand the code. Dan explains in his book and on his blog what's going on. Those "dreaded" pointer variables are at the heart of the scramble function. It's taken years for me to be able to "see" how they work. Keep studying C and you'll eventually be fluent. (The link above to the Tiny C program (file type .tc) shows how you "call" executables via C's system function.)

Throughout the book there are examples of things I've never seen before and also things that I have seen but which are done in a way I didn't know about. You've probably seen #define macros before but usually they are just defining constants like PI or MAXIN. Here's a fancier one:

#define repeat(a) for (int x = 0; x < a; x++)

He uses it in the add_word() function in randwords01.c.

const char *add_word(void)
{
	const char *vocabulary[] = {
		"orange", "grape", ...
	};
	int r;
	
	r = rand() % (sizeof(vocabulary)/sizeof(char *));
	return( vocabulary[r] );
}

int main()
{
	srand( (unsigned)time(NULL] );
	
	repeat(3)
		print("%s ", add_word() );
	putchar('\n');
	
	return(0);
}

I'd never heard of the archive utility ar which is used to build libraries. In Chapter 7, String utilities, a header file containing prototypes for functions like

char *left(char *s, int len);

clang -Wall -c first.c second.c third.c

Object files are created by this. You then use ar like so:

ar -rcs libmystring.a mystring.o

clang -Wall -L. libsample.c -lmystring

There are five more chapters in the book which I'll let you learn about on your own. I hope this review has sparked your interest.