BufferedReader

Note

This is a point-in-time snapshot of the API documentation from January 2026. Going forward, we will not be maintaining a public copy of these references, and recommend users to refer to the built-in signature helpers available in the Hack LSP instead for complete and up-to-date information.

Wrapper for ReadHandles, with buffered line-based byte-based accessors

• readLineAsync() is similar to fgets()
• readUntilAsync() is a more general form
• readByteAsync() is similar to fgetc()

Interface Synopsis

namespace HH\Lib\IO;

final class BufferedReader implements ReadHandle {...}

Public Methods

• ->__construct(ReadHandle $handle)
• ->getHandle(): ReadHandle
• ->isEndOfFile(): bool
  If we are known to have reached the end of the file
• ->linesIterator(): AsyncIterator<string>
  Iterate over all lines in the file
• ->readAllowPartialSuccessAsync(?int $max_bytes = NULL, ?int $timeout_ns = NULL): Awaitable<string>
• ->readByteAsync(?int $timeout_ns = NULL): Awaitable<string>
  Read a single byte from the handle
• ->readFixedSizeAsync(int $size, ?int $timeout_ns = NULL): Awaitable<string>
• ->readImpl(?int $max_bytes = NULL): string
• ->readLineAsync(): Awaitable<?string>
  Read until the platform end-of-line sequence is seen, or EOF is reached
• ->readLinexAsync(): Awaitable<string>
  Read a line or throw EPIPE
• ->readUntilAsync(string $suffix): Awaitable<?string>
  Read until the specified suffix is seen
• ->readUntilxAsync(string $suffix): Awaitable<string>
  Read until the suffix, or raise EPIPE if the separator is not seen

Public Methods (HH\Lib\IO\ReadHandle)

• ->readAllAsync(?int $max_bytes = NULL, ?int $timeout_ns = NULL): Awaitable<string>
  Read until there is no more data to read