Joy Online Manual
| NAME |
| objc:offsetPtr - Pointer arithmetic and type casting |
| SYNOPSIS |
objc:offsetPtr address offset ?type?
| DESCRIPTION |
| Returns address + offset * size, where size is the size of type if specified, otherwise the size of address's type. If the optional type parameter is given, the returned pointer points to the specified type, else it has the same type as address. |
| EXAMPLE |
| Allocates 100 bytes. |
joy> set p [objc:newPtr {char 100}]
char 100@0x218b78
| Adds 100 bytes to $p, returning a pointer to {char 100}. |
joy> objc:offsetPtr $p 1
char 100@0x218bdc
| Also adds 100 bytes to $p, returning a pointer to char. |
joy> objc:offsetPtr $p 100 char
char@0x218bdc
| Type-casts $p to a pointer to int |
joy> objc:offsetPtr $p 0 int
int@0x218b78
| SEE ALSO |
objc:newPtr
objc:peek
objc:poke
| KEYWORDS |
| pointer, type |
| Index |