In C language, the @ symbol has two meanings: Macro expansion operator: replaces the macro name with its definition. Address operator: returns the address of its operand, used for the address of a pointer pointing to a variable.
The meaning of the @ symbol in C language
In C language, the @ symbol has two main meanings:
1. Macro expansion operator
When the @ symbol is used for macro expansion, it will replace the macro name with its corresponding definition. For example:
#define MAX 100 int array[MAX];
When expanding the statement int array[MAX];
, the @ symbol replaces MAX
with its definition 100
, resulting in The following expanded statement:
int array[100];
2. Address Operator
When the @ symbol is used for address operations, it will return the address of its operand. The operand can be a variable, array element, or structure member. For example:
int x = 10; int *ptr = &x;
In this code, &x
represents the address of x, and ptr
points to the address. Therefore, *ptr
can access the value of variable x
.
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