Subject: [Boost-bugs] [Boost C++ Libraries] #2998: Make file_sink flushable
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2009-05-07 01:02:40
#2998: Make file_sink flushable
-------------------------------------------------------------+--------------
Reporter: Andrew Schweitzer <a.schweitzer.grps_at_[hidden]> | Owner: turkanis
Type: Feature Requests | Status: new
Milestone: Boost 1.39.0 | Component: iostreams
Version: Boost 1.38.0 | Severity: Not Applicable
Keywords: |
-------------------------------------------------------------+--------------
file_sink is hard to use as a debug log, since it does not flush.
For example, when used when pushed into a filtering_ostream with cout, if
flush is not called, characters don't appear on console or in file in a
timely fashion. If flush is called, the characters on the console appear
but not those in the file, because file_sink does not implement Flushable
concept, and doesn't flush.
This code:
filtering_ostream fo;
file_sink fsink("out.txt");
tee_filter<file_sink> tee_fsink(fsink);
fo.push(tee_fsink);
fo.push(cout);
fo << "some text";
fo.flush();
is very useful for arbitrary chains of debug logs, but not currently
usable.
The same issue applies to file, file_descriptor, and file_descriptor_sink.
If there is some reason these classes should not be modified to made
flushable, then it seems easy to make flushable_* versions. Example of
this attached, which was copied from file.hpp.
I also tried to add flushable_file_descriptor, by privately inheriting
from file_descriptor, and adding a flush call which calls
::FlushFileBuffers on handle()... but so far that doesn't seem to work, so
not attaching.
Discussion at
http://groups.google.com/group/boost-
list/browse_thread/thread/4c07e7c255e8143a/b9003b1b83c5a4db?lnk=raot&pli=1
-- Ticket URL: <https://svn.boost.org/trac/boost/ticket/2998> Boost C++ Libraries <http://www.boost.org/> Boost provides free peer-reviewed portable C++ source libraries.
This archive was generated by hypermail 2.1.7 : 2017-02-16 18:50:00 UTC