To learn C system programming, you need to master basic syntax, memory management, operating system interfaces, multi-threading and debugging tools. First, be familiar with the basic syntax of classes, pointers, references, arrays, etc., understand the difference between pointers and references, memory allocation and release timing, RAII ideas and smart pointers; second, master POSIX APIs such as fork(), exec(), pthread_create(), and understand thread synchronization, race conditions and atomic operations; second, be proficient in using GDB debugging, Valgrind to detect memory problems, and strace tracking system calls; finally, improve practical capabilities by implementing small projects such as shell interpreters, network communication programs, and log systems.

It is actually quite common to learn C to do system programming. C is suitable for this because it is close to the hardware, has good performance, and can operate memory directly. If you are writing operating systems, drivers, embedded systems or underlying tools, then this tutorial will help you clarify the direction.

Learn basic grammar and memory management well

In system programming, resource control is very important, so you have to first lay down the basic skills of C. For example, you must be familiar with classes, pointers, references, and arrays. Especially in memory management , the usages of new/delete, malloc/free cannot be errored, otherwise it will easily lead to memory leakage or segfault.

Suggested understanding of key points:

• The difference between pointers and references
• Memory allocation and release timing
• Design idea of ??RAII (resource acquisition is initialization)
• Use smart pointers (unique_ptr, shared_ptr) instead of naked pointers

For example, writing a simple memory pool under Linux or implementing your own string class is a good way to practice.

Familiar with operating system interfaces and multithreaded programming

System programming is inseparable from the interfaces provided by the operating system, such as file reading and writing, process control, signal processing, thread synchronization, etc. In this part, you need to master the APIs under the POSIX standard, such as how to use functions such as fork() , exec() , pthread_create() , and mmap() .

Multithreading programming is particularly important. C 11 has supported threads since the standard library, and you can use <thread></thread> and <mutex></mutex> for concurrent control. But also note:

• Avoid race conditions
• Use lock mechanism rationally
• Understand atomic operations and memory order

For example: you can write a multi-threaded server to listen to socket requests, and each connection opens a thread to process it. This kind of scenario is very common and can be practiced.

Master debugging and performance analysis tools

Writing the underlying code is prone to problems, and many problems are not easy to reproduce. At this time, you will rely especially on debugging tools and performance analysis methods. GDB must be used. In addition, Valgrind can check memory leaks, strace can track system calls, and perf can analyze hotspot functions.

Suggest you:

• Use GDB to set breakpoints, view stacks, and modify changes
• Check memory access out of bounds and leaks with Valgrind
• Use strace to see which system functions are called during the execution of the program

Only when the debugging capabilities improve will the development efficiency be higher. Especially when encountering problems such as segfault and deadlock, tools can help you quickly locate the cause.

Practical project recommendation

Just reading tutorials is not enough, the key is to do it. You can start with some small projects and slowly increase the difficulty. for example:

• Implement a simple shell interpreter (parse commands, create child processes)
• Writing TCP/UDP client and server communication programs
• Making a log system that supports multi-threaded write and log-level filtering
• Try writing a small memory management module

Although these projects are not complicated, they can help you string together the knowledge you have learned. And after making it, you can also write some actual content on your resume.

Basically that's it. System programming is a slow job that requires patience and practice. C is just the starting point as a tool. What is really important is the understanding of the system mechanism and hands-on ability. Don’t be afraid of getting stuck in pitfalls. Check more documents and read more source codes. Make progress naturally fast.

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