# ffi/read-bytes Read a byte range from native memory into a binary-safe Deft string — NUL bytes are preserved, unlike `ffi/string`. For buffer resources the range is bounds-checked. ## Syntax

[ffi/read-bytes $buf $offset $length]

## Parameters - `$buf` — native resource: a buffer from `ffi/alloc` (bounds-checked), or another resource whose pointer is read as a raw byte address (unchecked) - `$offset` — byte offset (number; negative values clamp to 0) - `$length` — byte count (number; negative clamps to 0; `0` returns `""`) ## Examples

set buf [ffi/alloc 8]
[ffi/write $buf 0 :u8 65]
[ffi/write $buf 1 :u8 0]
[ffi/write $buf 2 :u8 66]
set s [ffi/read-bytes $buf 0 3]    # → "A\0B" (length 3, NUL kept)
[ffi/read-bytes $buf 4 8]
# → %Err{:message "ffi/read-bytes: range exceeds buffer size"}
[ffi/read-bytes $buf 0 0]          # → ""
[ffi/close $buf]

## Returns A binary-safe string of the copied bytes. `%Err{:message}` for wrong arity, a non-resource argument, a closed resource, a null pointer, non-numeric offset/length, a buffer range past the end, or string allocation failure. Reading through a non-buffer resource performs no bounds checking. ## See Also `ffi/read`, `ffi/write`, `ffi/alloc`, `ffi/string`, `bytes/len`