Slides: Debugging Practice

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# Debugging Practice
## CSC 213 – September  2, 2026

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# Agenda for Today
1. Upcoming Work
2. C Practice
4. Debugging
5. Wrap Up

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# Upcoming Work

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# Assignment 1: Ngram Generator

**Due:** Tuesday, September 8th by 11:59pm

## Questions
*None so far.*

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# C Practice

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# C Practice: The Problem
We are going to write a C program called `charsort` together as a class (I will drive).
The program should do the following:

1. The program must accept exactly one string as a command line argument.
2. The output should be all of the letters in the input string, but printed in sorted order.

For example:
```shell
$ ./charsort hello
ehllo
```

Take a minute to consider how you might approach this problem and what you might need to look up to implement your approach.

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# C Practice: Live Coding

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# C Practice: Style Guide
Good C code should do the following:

.left-col[
- Indent every block of code
- Always use curly braces around blocks
- Write explanatory comments, with at least one by each block of code
- Cite resources in comments next to the relevant code
- Use descriptive variable names
- Use whitespace to break code into logical chunks
- Validate user input
- Print helpful error messages
]

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- Use standard library functions instead of re-implementing them.
- Try to follow modern C conventions
- Check return values from library functions
- Fix code that generates compiler warnings
- Use resources, and cite them appropriately
- Use local memory whenever possible (instead of calling `malloc`)
- Free allocated memory when you are done with it
]

**Is this list missing anything?**

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# Debugging

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# Discussion: Debugger Commands
For each `gdb` command below: what does it do, and when would you use it?
- `start`
- `continue`
- `break`
- `watch`
- `step`
- `next`

*Start by thinking of answers on your own. I will let you know when to start discussion.*

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# Debugging Exercise

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# Wrap Up

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# Reminders

## Assignment
The Ngram Generator assignment is due on Tuesday evening.
Start early so you have time to get stuck.

## Reading

- **The Abstraction: The Processes** (OSTEP, Chapter 4)
            
- **Interlude: Process API** (OSTEP, Chapter 5)
            
- **Mechanism: Limited Direct Execution** (OSTEP, Chapter 6)