What should be noted when using the C standard library?

When using the C language standard library, there are several points to note:

1. Include the correct header files: Functions and type definitions of the C standard library are contained in various header files, so before using standard library functions, the corresponding header files should be included. For example, to use the printf function in stdio.h, the header file should be included as #include .
2. Adhere to the rules of using functions: Functions in the standard library have their own rules for use, including the types of parameters and return values. When using these functions, it is important to follow the corresponding rules to avoid compilation errors or runtime errors.
3. Pay attention to the return value of functions: The return value of standard library functions is usually used to indicate the execution status or result of the function. When using these functions, it is important to handle the return value correctly to avoid errors.
4. Pay attention to memory management: Some functions in the standard library involve memory allocation and release, such as malloc and free functions. When using these functions, it’s important to correctly allocate and release memory to avoid issues like memory leaks or accessing illegal memory.
5. Avoid using deprecated functions: Some functions in the C standard library have been deprecated and are no longer recommended for use. When writing new programs, it is important to avoid using these deprecated functions to ensure program portability and compatibility.
6. Consider cross-platform compatibility: the C Standard Library is independent of the operating system, but there may be some differences on different operating systems. When writing cross-platform programs, it is important to pay attention to these differences and take appropriate measures to ensure the program runs smoothly on different operating systems.
7. Prevent buffer overflow: Some functions in the standard library, such as gets and scanf, carry the risk of buffer overflow. When using these functions, make sure that the length of input data does not exceed the size of the buffer to avoid data corruption or security vulnerabilities.
8. Pay attention to data type compatibility: standard libraries define some basic data types such as int and char. When using these types, be aware that the lengths and ranges of data types may differ on different platforms to avoid potential issues like data overflow or loss of precision.

In conclusion, when using the C language standard library, it is important to familiarize oneself with the rules of using the standard library, handle functions’ return values correctly, pay attention to memory management and cross-platform compatibility, avoid using deprecated functions, and prevent buffer overflow and data type compatibility issues.