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x/type/ptr

Raw pointers (Ptr) and the foreign-function interface (Ffi): the FFI surface for C interop.

ns ptr/ffi are de-registered; low-level/hot callers fetch-and-cache the prims. int->ptr is ns int (Ptr from-int).

Class Ptr

(Ptr from-int n)

Construct a pointer from an integer address (the int->ptr cast).

Parameters:

• n : INT — Integer address

Returns: PTR — A pointer to that address

(Ptr ptr? x)

Test whether a value is a raw pointer.

Parameters:

• x : ANY — Value to test

Returns: BOOL — True if x is a pointer

(Ptr ->int p)

The integer (address) representation of a pointer.

Parameters:

• p : PTR — A pointer

Returns: INT — Integer address

(Ptr ->str p)

Copy the NUL-terminated C string at P into a fresh x-lang string.

Parameters:

• p : PTR — A C string pointer

Returns: STRING — A new string (survives the C buffer)

(Ptr ref p off width)

Read a WIDTH-byte little-endian value at P+OFF.

Parameters:

• p : PTR — Base pointer
• off : INT — Byte offset
• width : INT — Read width in bytes (1,2,4,8)

Returns: INT — The value read

(Ptr set! p off v width)

Write a WIDTH-byte little-endian value V at P+OFF.

Parameters:

• p : PTR — Base pointer
• off : INT — Byte offset
• v : INT — Value to store
• width : INT — Write width in bytes

Returns: ANY — nil

(Ptr ref-word p off)

Read one machine word (sizeof(long)) at P+OFF.

Parameters:

• p : PTR — Base pointer
• off : INT — Byte offset

Returns: INT — The word value

(Ptr set-word! p off v)

Write one machine word V at P+OFF.

Parameters:

• p : PTR — Base pointer
• off : INT — Byte offset
• v : INT — Word value to store

Returns: ANY — nil

(Ptr call p . args)

Call a C function pointer with string arguments.

Parameters:

• p : PTR — C function pointer
• args : STRING — String arguments (variadic)

Returns: INT — The C return value

Class Ffi

(Ffi dlopen path mode)

Load a shared library.

Parameters:

• path : STRING — Library file path (() for the main program)
• mode : INT — dlopen mode flags (e.g. 1 = RTLD_LAZY)

Returns: PTR — Library handle, or () on failure

(Ffi dlsym lib name)

Look up a symbol in a loaded library.

Parameters:

• lib : PTR — Library handle from dlopen
• name : STRING — Symbol name

Returns: PTR — Function or data pointer

(Ffi call sig lib . args)

Invoke a C function through the typed-signature FFI bridge.

Parameters:

• sig : STRING — Calling signature (e.g. “d+d”, “s0->d”)
• lib : ANY — Library handle, or () for a built-in signature
• args : ANY — Call arguments (variadic)

Returns: ANY — The converted C return value