What is the standard function name in C language

C language standard function names are predefined names of functions provided by the C standard library to perform various tasks such as input/output, string operations, mathematical calculations, and memory management. Naming conventions typically include starting letters, lowercase letters, numbers, or underscores, and using snake-like uppercase and lowercase letters for functions that name multiple words. Commonly used functions include printf() and scanf() for input/output, strcpy() and strcmp() for string operations, sqrt() and sin() for mathematical calculations, and memory management. malloc() and free() etc.

The standard function name of C language

The standard function name of C language refers to the standard function name provided by the C standard library The predefined name of the function. These functions are used to perform various tasks such as input/output, string manipulation, mathematical calculations, and memory management.

Naming convention

Standard function names generally use the following naming convention:

• Start with a letter, followed by lowercase letters, numbers, or underscores.
• A function that uses lower camel case to name multiple words.
• Function ending with the letter "r" or "f" means returning a value.
• Functions ending with the letter "v" do not return any value.

Common standard functions

The following are some commonly used standard functions:

• Input/output :

  • printf() and scanf(): used to print and read formatted data.
  • fopen() and fclose(): used to open and close files.
  • fread() and fwrite(): used to read and write data from files.

• String operations:

  • ##strcpy() and strcat() : Used for copying and concatenating strings.
  • strcmp() and strncmp(): used to compare strings.
  • strlen(): Used to get the length of a string.

• Mathematical calculations:

  • sqrt(): Used to calculate square roots.
  • sin() and cos(): used to calculate trigonometric functions.
  • pow(): Used to calculate exponentiation operations.

• Memory management:

  ##malloc()
  • and free(): used to allocate and release memory.
  realloc()
  • : Used to reallocate memory.

Using standard functions

To use standard functions, you need to include the corresponding header file in the program. For example, when using input/output functions, you need to include the

stdio.h

header file. The syntax and parameter lists of standard functions can be found in the C standard library documentation.

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