& (reference operator)
Description
Referencing is one of the features specifically for use with pointers. The ampersand operator
&
is used for this purpose. If x
is a variable, then &x
represents the address of the variable x
.Example Code
1int *p; // declare a pointer to an int data type2 int i = 5;3 int result = 0;4 p = &i; // now 'p' contains the address of 'i'5 result = *p; // 'result' gets the value at the address pointed by 'p'6 // i.e., it gets the value of 'i' which is 5
Notes and Warnings
Pointers are one of the complicated subjects for beginners in learning C, and it is possible to write the vast majority of Arduino sketches without ever encountering pointers. However for manipulating certain data structures, the use of pointers can simplify the code, and knowledge of manipulating pointers is handy to have in one’s toolkit.
See also
Suggest changes
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License
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