pocketpy/docs/modules/stdc.md

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icon: package

label: stdc

stdc

Typed native storage and raw-memory operations for C bindings.

Typed storage

from stdc import Int32, addressof, sizeof

value = Int32(42)
assert value.value == 42
Int32.write(addressof(value), 0, 100)
assert value.value == 100

items = Int32.array(3)
items[0] = 10
items[1] = 20
items[2] = 30
assert Int32.read(addressof(items), 1) == 20
assert sizeof(Int32) == 4

Type(value) creates scalar storage; Type.array(length) creates an array. The wrapper keeps that storage alive. Initialize array elements before reading them. read(pointer, offset) and write(pointer, offset, value) use offsets in elements of the selected type, not bytes.

Family	Types
C integers	Char, UChar, Short, UShort, Int, UInt, Long, ULong, LongLong, ULongLong
Fixed widths	Int8/16/32/64, UInt8/16/32/64
Other C values	Float, Double, Bool, Pointer
Platform sizes	SizeT, IntPtrT, UIntPtrT

Use sizeof(type) to query the native size rather than assuming a platform's long or pointer width.

Raw memory

The module exposes malloc, free, memcpy, memset, memcmp, read_cstr, write_cstr, read_bytes, and write_bytes. Pointer values are integers.

These operations do not provide Python's memory safety. Validate addresses, sizes, and ownership; retain the wrapper while its address is in use. Allocate enough space for string terminators, and free manually allocated memory exactly once. Do not call free() on memory owned by a typed wrapper.

Full signatures: stdc.pyi. Runtime type names follow stdc.c.