Use std::source_location::current() as the default parameter to automatically capture the file name, line number and function name of the call point; 2. You can simplify log calls through macros such as #defineLOG(msg)log(msg,std::source_location::current()); 3. You can expand the log content with log level, timestamp and other information; 4. To optimize performance, function names can be omitted or location information can be disabled in the release version; 5. Column() and other details are rarely used, but are available. Using std::source_location can significantly improve the debugging value of logs with extremely low overhead without manually passing in FIL

The basic usage of std::vector includes: 1. Declare vector; 2. Add elements with push_back(); 3. Initialize with initialization list; 4. Loop traversal with range for; 5. Access elements through index or back(); 6. Direct assignment of values to modify elements; 7. Delete the end elements with pop_back(); 8. Call size() to get the number of elements; it is recommended to use constauto& to avoid copying, pre-allocate reserve() to improve performance, and pay attention to checking that it is not empty before access. This data structure is an efficient and preferred way to handle string lists.

Use the seekg and tellg methods of std::ifstream to obtain file size across platforms. By opening a binary file and positioning it to the end, use tellg() to return the number of bytes; 2. It is recommended to use std::filesystem::file_size for C 17 and above. The code is concise and errors are handled through exceptions. The C 17 standard must be enabled; 3. On POSIX systems, the stat() function can be used to efficiently obtain file size, which is suitable for performance-sensitive scenarios. The appropriate method should be selected based on the compiler and platform, and std::filesystem should be used first (if available), otherwise use ifstream to ensure compatibility, or use st on Unix systems

memory_order_relaxed is suitable for scenarios where only atomicity is required without synchronization or order guarantee, such as counters, statistics, etc. 1. When using memory_order_relaxed, operations can be rearranged by the compiler or CPU as long as the single-threaded data dependency is not destroyed. 2. In the example, multiple threads increment the atomic counter, because they only care about the final value and the operation is consistent, the relaxed memory order is safe and efficient. 3. Fetch_add and load do not provide synchronization or sequential constraints when using relaxed. 4. In the error example, the producer-consumer synchronization is implemented using relaxed, which may cause the consumer to read unupdated data values because there is no order guarantee. 5. The correct way is

Operator overloading in C allows new behaviors of standard operators to be assigned to custom types, 1. Return new objects through member function overloading; 2. Overload = Modify the current object and return reference; 3. Friend function overloading

The answer is that writing a simple TCP client and server requires the socket programming interface provided by the operating system. The server completes communication by creating sockets, binding addresses, listening to ports, accepting connections, and sending and receiving data. The client realizes interaction by creating sockets, connecting to servers, sending requests, and receiving responses. The sample code shows the basic implementation of using the Berkeley socket API on Linux or macOS, including the necessary header files, port settings, error handling and resource release. After compilation, run the server first and then run the client to achieve two-way communication. The Windows platform needs to initialize the Winsock library. This example is a blocking I/O model, suitable for learning basic socket programming.

Falsesharing occurs when multiple threads modify different variables in the same cache line, resulting in cache failure and performance degradation; 1. Use structure fill to make each variable exclusively occupy one cache line; 2. Use alignas or std::hardware_destructive_interference_size for memory alignment; 3. Use thread-local variables to finally merge the results, thereby avoiding pseudo-sharing and improving the performance of multi-threaded programs.

To use regular expressions in C, you need to include header files and use the functions it provides for pattern matching and text processing. 1. Use std::regex_match to match the full string, and return true only when the entire string conforms to the pattern; 2. Use std::regex_search to find matches at any position in the string; 3. Use std::smatch to extract the capture group, obtain the complete match through matches[0], matches[1] and subsequent sub-matches; 4. Use std::regex_replace to replace the matching text, and support the capture group with references such as $1 and $2; 5. You can add an iset when constructing the regex (