readImpl
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.
An immediate, unordered read
public function readImpl(
?int $max_bytes = NULL,
): string;
Parameters
?int $max_bytes = NULLthe maximum number of bytes to read- if
null, an internal default will be used. - if 0,
EINVALwill be raised. - up to
$max_bytesmay be allocated in a buffer; large values may lead to unnecessarily hitting the request memory limit.
Returns
string