#include <sicstus/sicstus.h> spio_t_error_code SP_fclose( SP_stream *stream, spio_t_bits close_options);
Close the stream.
The stream to close unless the
set, see below.
The following bits can be set:
Close the specified directions. If neither of these options is specified, the stream is closed in all opened directions, i.e. as if both options were specified. If the stream is not opened in a direction specified by an option, that option is ignored.
Note that it is possible to close only one direction of a bidirectional stream. The return value will tell whether the stream is still open; see below.
Close the specified direction forcibly, i.e. without flushing buffers etc. This also ensures that the close finishes quickly, i.e. does not block.
Do not use OS
fclose() or similar when closing a stream in
write direction, i.e. do not wait for written data to reach the
By default, closing a stream will try to ensure that all written data have been stored on disk before the call returns. This makes stream handling more robust, e.g. if the process crashes shortly after closing the stream. However, waiting for data to reach the disk is sometimes very slow (e.g. on some Linux configurations), in which case this flag can be used to speed things up, at the cost of somewhat reduced robustness.
You should avoid using this option.
Pass non-blocking option to lower level routines, including the call
SP_flush_output() that is issued when non-forcibly closing write
One possible use for this option is to perform a best effort
close, which falls back to using
SP_FCLOSE_OPTION_FORCE only if
ordinary close would block.
In this case the stream should not be a stream but instead be
user_class of a user defined stream. When this option is
passed, all currently opened streams of that class is closed, using
the remaining option flags. E.g. to close all user defined streams
of class my_class in the read direction only do:
On success, all specified directions has been closed. Since some direction may still be open, there are two possible return values on success:
The stream is still valid, some direction is still not closed.
The stream has been deallocated and cannot be used further. All directions have been closed.
On failure, returns a SPIO error code. Error codes with special meaning
SP_fclose() are the same as for
see. Other error codes may also be returned.
cpg-ref-SP_flush_output. Prolog Streams.