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What does ** mean in C?
- Thread starter trivektor
- Start date
It's like this...
Code:
char c; /* c is a character */
char * pc; /* pc is a pointer to a character */
char ** ppc; /* ppc is a pointer to a pointer to a character */
/* and the following are equivalent */
char ** argv;
char * argv[];
char argv[][];Warning - illegal declarator:
C and C++ declarations pattern:
type_name list_of_declarators;
char **argv - (**argv) is a declarator. Suppose we have **argv in an expression. An asterisk sign denotes unary dereferencing operator in this context. So we have:
(*(*argv)) expression. Well, argv must be a pointer (only a pointer is a legal operand of unary * operator). Now *argv returns a pointer (for the second * operator). We have a pointer to a pointer. Look at the char type: argv must be pointer to pointer to char...
Code:
char argv[][];type_name list_of_declarators;
char **argv - (**argv) is a declarator. Suppose we have **argv in an expression. An asterisk sign denotes unary dereferencing operator in this context. So we have:
(*(*argv)) expression. Well, argv must be a pointer (only a pointer is a legal operand of unary * operator). Now *argv returns a pointer (for the second * operator). We have a pointer to a pointer. Look at the char type: argv must be pointer to pointer to char...
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