linux c 字符串常量定义的几种方式

2024年4月17日发(作者：)

linux c 字符串常量定义的几种方式

英文版

Title: Several Methods of Defining String Constants in Linux

C

In the Linux C programming environment, defining string

constants is a fundamental task that often arises. Here are

several common methods to accomplish this:

Direct Assignment:

The simplest way to define a string constant is by directly

assigning it to a character array. For example:

cCopy char str[] = "Hello, World!";

char str[] = "Hello, World!";

In this case, the compiler automatically allocates memory for

the array, including the null terminator.

2. Using String Literals:

String literals are constant character arrays that can be

assigned to pointer variables. However, modifying a string literal

is undefined behavior. For instance:

cCopy char *ptr = "Hello, World!";

char *ptr = "Hello, World!";

Here, ptr points to a read-only memory location where the

string literal is stored.

3. Using the const Keyword:

When you want to ensure that a string won't be modified,

you can use the const keyword. This is especially useful when

passing strings to functions that shouldn't modify them:

cCopy const char *constStr = "Immutable String";

const char *constStr = "Immutable String";

Initializing with String Literals and Modifying Copies:

If you want to modify a string while still using a string literal

as a starting point, you can create a copy of the string literal

and then modify that copy:

cCopy char modifiableStr[] = "Original String";