Scanf and fgets are two commonly used functions available in the C language. While they may sound similar in terms of input, they are actually quite different in terms of data they can handle and the way they handle input. Understanding the difference between these two is essential to properly utilizing them.
The biggest difference between scanf and fgets is their purpose. Scanf is designed to read formatted data from the standard input stream, while fgets is designed to read text lines from a file.
Scanf is just for reading data from user standard input, whereas fgets is for reading data from a file. This means if you want to read from the user, then scanf is the better choice. If you need to read a line from a file, then you should use fgets.
2. Data Structure
Another significant difference between scanf and fgets is the data structure they work with. Scanf can read basic data types such as int, float, double and char, while fgets can only read strings.
Scanf is type safe and is the right choice if you need to read basic data types such as integers, floats, doubles and characters. On the other hand, fgets is better suited for strings as it can only return a pointer to the resulting string.
Scanf supports formatting of data while reading, while fgets does not. This means that you can use different specifiers to specify the structure of the input data in scanf. For example, you can use %d for integers and %f for floats. On the other hand, fgets does not use any formatting and is strictly for reading text.
Scanf is great for when you need to read formatted data, you can easily specify the type of data in the format string. Fgets, on the other hand, is not suitable for formatted data and is only useful for reading lines of text.
4. Buffer Size
Another difference between scanf and fgets is the size of the buffer they work with. Scanf will read up to a specified number of characters from the input, while fgets reads up to a specific size of the line.
This means that if you are using scanf for a long line, you need to specify a large enough buffer size. On the other hand, fgets does not require you to specify a buffer size and will read up to the size of the line.
5. Error Handling
Scanf does not provide any error handling while Fgets does. Fgets sets the global error variable “errno” to indicate if there was an error while reading. This is useful for detecting errors in file operations.
Scanf does not have any error handling and simply returns the number of items it was able to read successfully. This makes it difficult to detect errors while reading data. Fgets, on the other hand, provides an additional level of error handling by setting the global error variable “errno”.
Scanf is not considered secure for input as it does not perform any type of validation on the input. In addition, it does not include any mechanism for input sanitization or buffer overflow protection. This makes it vulnerable to buffer overflow attacks.
Fgets is considered more secure than scanf as it can be used to validate input and enforce limits on the length of input. In addition, Fgets includes built-in input sanitization, making it less vulnerable to buffer overflow attacks.
The syntax for scanf and fgets is also slightly different. Scanf takes two arguments, a format string and a variable to store the result, while fgets takes three arguments, a pointer to a buffer to store the result, a maximum length of the line and a stream to read from.
Scanf is a more concise function as it only requires two arguments while Fgets requires three. However, the third argument in Fgets provides more control than scanf, allowing the user to specify a maximum length and the stream to read from.
Scanf is generally faster than fgets as it only needs to read data from the standard input stream. It is also less memory intensive as it does not require any additional memory to store the data.
Fgets, on the other hand, is slower as it needs to read from a file or a stream. It is also memory intensive as it needs a buffer to store the data it reads from the file or stream.
Scanf and fgets are both portable functions, but fgets has better cross-platform compatibility than scanf. This is because it is designed to read from a file, which can be found on all platforms, while scanf is designed to read from the standard input, which might not be available on all platforms.
Scanf and fgets are both portable functions, but fgets is more likely to have full compatibility on all platforms due to its ability to read from a file. Scanf can only read from the standard input, which might not be available on all platforms.
Scanf and fgets are both commonly used functions in the C language. While they may sound similar, they work differently and can be used for different purposes. Scanf is typically used for reading data from the user, while fgets is used for reading line by line from a file. They also differ in terms of data structure, formatting, buffer size, error handling, security, syntax, speed and portability.
Understanding the differences between scanf and fgets is essential for properly utilizing them. Knowing when to use scanf and when to use fgets can help you write more efficient code and ensure your programs work on all platforms.