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(librep.info)Streams

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Streams
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   A "stream" is a Lisp object which is either a data sink (an "output
stream") or a data source (an "input stream"). All streams produce or
consume sequences of 8-bit characters.

   Streams are very flexible, functions using streams for their input
and output do not need to know the type of stream being accessed. For
example the Lisp reader (the `read' function) takes an input stream as
its sole argument, it then reads characters from this stream until it
has parsed a whole object. This stream could be a file, a function, or
even a string; the `read' function does not need to differentiate.

 - Function: streamp arg
     Return true if ARG is a stream.

 - Function: input-stream-p arg
     Return true if ARG is an input stream.

 - Function: output-stream-p arg
     Return true if ARG is an output stream.

Input Streams

Types of input stream

Output Streams

Types of output stream

Input Functions

Functions to read from streams

Output Functions

How to output to a stream

Formatted Output

Output by template