17 The STREAM package

stream-read-char-no-hang

Generic Function

Summary

Returns either a character from the stream, an:EOF if the end-of-file is reached, ornil if no input is currently available.

Package

stream

Signature

stream-read-char-no-hang stream => result

Arguments

stream: A stream.

Values

result: Either a character, an:EOF symbol, ornil.

Description

The generic functionstream-read-char-no-hang implementsread-char-no-hang. It returns either a character read from the stream, an:EOF if end-of-file is reached, ornil if no input is available. The default method provided byfundamental-character-input-stream simply callsstream-read-char which is sufficient for file streams, but interactive streams should define their own method.