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Deno.ReaderSync - Deno documentation
interface Deno.ReaderSync
Deprecated

This will be removed in Deno 2.0. See the Deno 1.x to 2.x Migration Guide for migration instructions.

An abstract interface which when implemented provides an interface to read bytes into an array buffer synchronously.

Methods

readSync(p: Uint8Array): number | null

Reads up to p.byteLength bytes into p. It resolves to the number of bytes read (0 < n <= p.byteLength) and rejects if any error encountered. Even if readSync() returns n < p.byteLength, it may use all of p as scratch space during the call. If some data is available but not p.byteLength bytes, readSync() conventionally returns what is available instead of waiting for more.

When readSync() encounters end-of-file condition, it returns EOF (null).

When readSync() encounters an error, it throws with an error.

Callers should always process the n > 0 bytes returned before considering the EOF (null). Doing so correctly handles I/O errors that happen after reading some bytes and also both of the allowed EOF behaviors.

Implementations should not retain a reference to p.

Use iterateReaderSync to turn ReaderSync into an Iterator.