November 2008 - Boost-users

Simple threading question (I hope)
by Alec Munro 15 Nov '08

15 Nov '08

Hi List, I'm fairly new to multithreading, especially in C++. Things seem generally straightforward when using boost::thread, but there was one question I had. I have a mutex that I use to control access to a data processing object. Whenever I receive new data, I attempt to lock the mutex, and process it. However, I think it's possible that I might receive several data packets while I'm processing, and it's important that these packets are processed in order. So I suppose my question is, when a mutex is unlocked, how is it determined which thread gets to lock it next? Thanks, Alec Munro --------------------------------------------------------------------- This transmission (including any attachments) may contain confidential information, privileged material (including material protected by the solicitor-client or other applicable privileges), or constitute non-public information. Any use of this information by anyone other than the intended recipient is prohibited. If you have received this transmission in error, please immediately reply to the sender and delete this information from your system. Use, dissemination, distribution, or reproduction of this transmission by unintended recipients is not authorized and may be unlawful.

4 6

[swap] boost::swap roadmap?
by JOAQUIN M. LOPEZ MUÑOZ 15 Nov '08

15 Nov '08

Hello, Is Boost.Swap going to make it into Boost 1.38? Thank you, Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

2 2

Re: [Boost-users] Boost Static Linking Woes
by Brian Dawn 15 Nov '08

15 Nov '08

Alright, I recompiled boost with runtime-link=static but I got the same error. >> After doing this, I guess there is some "magic" preprocessor define you need to specify in your project, so the boost config header becomes aware of what boost variant you are using... I have looked for some sort of preprocessor definition for static builds, but I couldn't seem to find any. Does anyone happen to know what this is/could be? >> I believe the only exception to this is Boost.Python, but that has special requirements that make static linking much more tricky I believe. I actually am linking to Boost.Python, and Boost.Filesystem (both really nice libraries). However I probably should have said earlier, but I receive 2 "Mixing a dll boost library with a static runtime is a really bad idea..." errors. I assume 1 is for python and the other for filesystem? Any help is appreciated, I really need these to be statically linked. Thanks everyone! -Brian.

2 2

Regex - Reading CSV files like MS Excel does
by Jeff Dunlap 14 Nov '08

14 Nov '08

The expression regex e(",") handles files in a clean format such as: field 1,field 2,field 3 I would like to read some CSV files where there may be fields that contain a comma (enclosed in ""): 1999,Smith, Mike, "Smith, Mike", 55 1999,Doe, Jane, "Doe, Jane", 45 And if possible, I would like to handle commas and quotes within the field: 1999,Doe, Jane, "Doe, Jane "Happy Gurl"", 45 Can someone help me with this please? Thank you very much

4 5

Using threads without RTTI enabled
by Rick Meier 14 Nov '08

14 Nov '08

Is there some way to use threads without needing rtti? To be more specific it looks like threads.hpp includes function_base.hpp and lexical_cast.hpp. Both of these files reference typeid. Is there something I can do to get around this? Thanks Rick M

1 0

[Proto] Functions returning an expression
by Joel Falcou 14 Nov '08

14 Nov '08

I have a DSL defined in proto. What's the best wayt o build functions that returns an expression made of this DSl elements. Like let's say the vec_expr class support+-*/ operators I want to write ??? f( vec_expr<W> const& a, vec_expr<Y> const& b) { return (a+b)/(a-b); } How can I easily (aka no nested make_expr call) build the return type ? TIA -- ___________________________________________ Joel Falcou - Assistant Professor PARALL Team - LRI - Universite Paris Sud XI Tel : (+33)1 69 15 66 35

2 4

Always have posting & responding to messages here
by Jeff Dunlap 14 Nov '08

14 Nov '08

First, I would like to thank the kind individuals who have helped me in the past--I can never thank anyone because I simply cannot respond to messages. This web interface never seems to show up to date information so messages that I post via the web interface do not appear on the web interface for some weird reason, no matter if I choose the refresh dropdown option or go to the home page and navigate to this group. I am able to see current messages via outlook express, but cannot post using it unfortunately. Is this just the way this works or are there other options available for posting/reading? Thanks in Advance

2 2

Re: [Boost-users] boost signals2 review
by Stjepan Rajko 14 Nov '08

14 Nov '08

Thank you, Andy, for the review. Stjepan On Mon, Nov 10, 2008 at 9:18 AM, Andrew Webber <andy(a)aligature.com> wrote: > For this review, I have focused on the usability and documentation of the > new signals2 library. I haven't really probed into the implementation and > so I'm assuming that the code is adequate and mostly bug free. > > In general, I think that this library should be accepted as a boost > library. Other than a few questions and annoyances, I think the library is > an extremely welcome addition to the boost libraries. > > I think that the interface changes required to guarantee thread safety are > understandable. I've seen some discussion on the mailing list about > retaining the trackable interface for backwards compatibility. While I > understand the desire to keep the changes required by switching to signals2 > to a minimum, I think signals2 provides a clean break. I understand > boost::signals is going to be maintained for the time being. This way, if > people don't want to change, they don't need to for the time being. If they > want thread safe signals, they should switch to the new library, its new > techniques and its clean interface. > > Here are my specific comments: > * Why the change to boost::optional for signal return values. Maybe I > missed a discussion about the motivation on the mailling list, but this is > an interface change that appears to be unnecessary. > > * I would like to see examples provided to explain the use of > postconstructable, predestructable, and deconstruct_ptr. I think a concrete > example might clear up some people's confusion over when it's appropriate to > use these. > > * I'd also like to see a concrete example shown of switching out the mutex > class used. I think three examples would be best: built-in, dummy_mutex, > and boost::mutex. > > * I'm not very happy about the tendancy of the slot disconnect exceptions > to show up in Visual Studio output. For instance, I built a test program > where several tracked objects were destroyed from different threads, based > on a random timer, while the slot was being invoked over and over. The > program worked well except for a great deal of repeated output like the > following: > > First-chance exception at 0x7c812a5b in SignalsTest.exe: Microsoft C++ > exception: > boost::exception_detail::clone_impl<boost::exception_detail::error_info_injector<boost::bad_weak_ptr> >> at memory location 0x0012dc0c.. > First-chance exception at 0x7c812a5b in SignalsTest.exe: Microsoft C++ > exception: boost::signals2::expired_slot at memory location 0x0012df58.. > > > I did several experiments with this library on Microsoft Visual Studio > 2005. I did not encounter any bugs or problems during my testing. I have a > decent amount of experience in this problem domain. In the past, I have > implemented a (limited) thread safe wrapper around the boost::signals > library. The signals2 library would very effectively replace my wrapper. I > spent a couple of hours on my evaluation, I would consider it moderately > in-depth without evaluating the signals2 implementation. > > Best, > Andy Webber > >

3 2

Problem at the asynchronous TCP Server example
by Daniel França 14 Nov '08

14 Nov '08

Hi everyone, I'm new at this list and new using the boost library. I'm little by little learning about boost. Now I was trying to do this example: http://www.boost.org/doc/libs/1_36_0/doc/html/boost_asio/tutorial/tutdaytim… The source is here: http://www.boost.org/doc/libs/1_36_0/doc/html/boost_asio/tutorial/tutdaytim… But when I try to link I get this errors: /usr/include/boost/system/error_code.hpp undefined reference to `boost::system::get_posix_category()' The program is linking with the follows boost librarys: boost_filesystem-gcc42-mt boost_system-gcc42-mt boost_unit_test_framework-gcc42-mt Maybe I forgot something when I did compile boost? My version of boost is 1.36. I use Linux (Slackware 12.1 + KDE 4.1), gcc 4.2.3 and Eclipse+CDT Best Regards -- Daniel C. França Tecnosapiens: http://tecnosapiens.wordpress.com 24Quadros: http://24quadros.wordpress.com -- Daniel C. França Tecnosapiens: http://tecnosapiens.wordpress.com 24Quadros: http://24quadros.wordpress.com

1 0

Problem with Serialization and Intel 10.0.023
by Steve Nolen 14 Nov '08

14 Nov '08

2 1