How to use scanf_s in c language

The scanf_s function in C language is a safe formatted input function, used to prevent security issues such as input buffer overflow. The steps are: 1. Specify the input format string; 2. Pass the variable address as a parameter to the function; 3. Call the scanf_s function to read the input; 4. Check the function return value to ensure success. Advantages include security, robustness, and formatted input control.

Usage of scanf_s in C language

The scanf_s function is a safe formatted input function in C language , which prevents security issues such as input buffer overflows.

Usage Syntax:

<code class="c">int scanf_s(const char *format, ...);</code>

Parameters:

• format: points to the input format Pointer to string
• ...: Variable length variable list to read

Return value:

The function returns the number of successfully read input items, or EOF if an error occurs.

Usage steps:

1. Specify the input format string.
2. Pass the address of the variable as a parameter to the function.
3. Call the scanf_s function to read input.
4. Check the function return value to ensure success.

Advantages:

• Security: Prevent input buffer overflow, thereby improving code security.
• Robustness: Ensures normal operation under various input conditions.
• Formatted input: Provides formatting control of input data.

Example:

To read an integer and a floating point number, you can use the following code:

<code class="c">int num;
float fnum;
scanf_s("%d %f", &num, &fnum);</code>

Notes :

• When using scanf_s, you must include the <stdio.h> header file.
• The input format string must match the variable type.
• For string input, you need to use the %s format specifier and provide the address of a character array.

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