Why are C Character Literals Represented as Integers?

Why are C character literals integers and not characters?

In the world of programming, characters are typically represented by single-byte integers. This is true for most programming languages, including C. However, C character literals are an exception to this rule. They are actually represented as integers, rather than characters. This can be surprising for newcomers to the language, who might expect character literals to behave like characters.

The rationale behind this design decision is rooted in the history of the C language. When Dennis Ritchie was developing C, he wanted to keep the language as small and efficient as possible. One way he did this was to represent character literals as integers. This allowed him to save space and memory, which was a critical concern at the time.

While this design decision may have made sense at the time, it can be a source of confusion for programmers today. For example, the following code will print the value 97:

printf("%d", 'a');

This is because 'a' is represented as an integer, and the printf() function expects an integer as its argument. If you want to print the character 'a', you need to use the %c format specifier:

printf("%c", 'a');

This will print the character 'a', as expected.

The distinction between character literals and integers can also be important when working with pointers. For example, the following code will create a pointer to an integer:

int *p;

However, the following code will create a pointer to a character:

char *p;

This is because 'a' is represented as an integer, and the compiler will infer that p is a pointer to an integer. If you want to create a pointer to a character, you need to use the following syntax:

char *p = "a";

This will create a pointer to the character 'a'.

The distinction between character literals and integers can be a bit confusing at first, but it is important to understand if you want to write correct C code. By following the tips above, you can avoid common pitfalls and write code that is both efficient and correct.

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