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(libc.info)Other Kinds of Streams

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Other Kinds of Streams
======================

   The GNU library provides ways for you to define additional kinds of
streams that do not necessarily correspond to an open file.

   One such type of stream takes input from or writes output to a
string.  These kinds of streams are used internally to implement the
`sprintf' and `sscanf' functions.  You can also create such a stream
explicitly, using the functions described in Note: String Streams.

   More generally, you can define streams that do input/output to
arbitrary objects using functions supplied by your program.  This
protocol is discussed in Note: Custom Streams.

   *Portability Note:* The facilities described in this section are
specific to GNU.  Other systems or C implementations might or might not
provide equivalent functionality.

String Streams

Streams that get data from or put data in

a string or memory buffer.

Obstack Streams

Streams that store data in an obstack.

Custom Streams

Defining your own streams with an arbitrary

input data source and/or output data sink.