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_variant_t question ... Hadi Rezaee19-Oct-01 12:58 Hadi Rezaee 19-Oct-01 12:58  Hi all, What is return value in this code: &(_variant_t("Hadi")) I mean, return value is what kind of data types ? My month article: Game programming by DirectX by Lan Mader. Please visit in: www.geocities.com/hadi_rezaie/index.html Hadi Rezaie Re: _variant_t question ... Christian Graus19-Oct-01 14:58 Christian Graus 19-Oct-01 14:58  surely a pointer to a variant with a char * in it ? If you want a WCHAR, then you'd do this &(_variant_t(L"Hadi")) Doing this would make me nervous - I don't know what would happen because you're returning the address of a variable which you're creating in the same line and is about to go out of scope. If I have to return a pointer, I create it first and don't delete it ( obviously ), so the returning function has responsibility for clearing the memory. Christian As I learn the innermost secrets of the around me, they reward me in many ways to keep quiet. Men with pierced ears are better prepared for marriage. They've experienced pain and bought Jewellery. Re: _variant_t question ... Hadi Rezaee20-Oct-01 12:42 Hadi Rezaee 20-Oct-01 12:42  It is all the source code: long lArray = 0; COleSafeArray ole_array; ole_array.CreateOneDim(VT_VARIANT, 1); ole_array.PutElement(&lArray, &(_variant_t("NAME"))); I read MSDN, i must pass void * value to second parameter in PutElement, but in this example he wrote: &(_variant_t("NAME")) !!! I can't understand help me ... My month article: Game programming by DirectX by Lan Mader. Please visit in: www.geocities.com/hadi_rezaie/index.html Hadi Rezaie Re: _variant_t question ... Christian Graus20-Oct-01 13:04 Christian Graus 20-Oct-01 13:04  Yes, but it's not in a return statement, like your first example, and therefore is not deleted because it is still in scope during the call. Christian As I learn the innermost secrets of the around me, they reward me in many ways to keep quiet. Men with pierced ears are better prepared for marriage. They've experienced pain and bought Jewellery. Re: _variant_t question ... Michael Dunn19-Oct-01 16:05 Michael Dunn 19-Oct-01 16:05  That creates a new _variant_t object and returns its address. However that is a temporary object, and gets destroyed at the end of whatever statement it's in, so you can't use that as a function return value, because the pointer will be invalid back in the calling code (it won't point at a valid object). --Mike-- http://home.inreach.com/mdunn/ "....." -- Silent Bob your with and Re: _variant_t question ... Hadi Rezaee20-Oct-01 12:44 Hadi Rezaee 20-Oct-01 12:44  I see your website, that is nice !!! By the way, It is all the source code: long lArray = 0; COleSafeArray ole_array; ole_array.CreateOneDim(VT_VARIANT, 1); ole_array.PutElement(&lArray, &(_variant_t("NAME"))); I read MSDN, i must pass void * value to second parameter in PutElement, but in this example he wrote: &(_variant_t("NAME")) !!! I can't understand help me ... My month article: Game programming by DirectX by Lan Mader. Please visit in: www.geocities.com/hadi_rezaie/index.html Hadi Rezaie Re: _variant_t question ... Michael Dunn20-Oct-01 15:59 Michael Dunn 20-Oct-01 15:59  As I said already, that makes a new temporary _variant_t object and takes its address. That address is passed to the PutElement() function. Since by C++ rules, any pointer can be implicitly converted to void*, no cast is needed. --Mike-- http://home.inreach.com/mdunn/ "....." -- Silent Bob your with and throw and catch Joe Moldovan19-Oct-01 11:45 Joe Moldovan 19-Oct-01 11:45  Does anyone know how to throw an exception across threads? Is this possible at all given the stack unwinding issues? Is there perhaps some other mechanism for interrupting the logic of one thread from another without Waits or SleepEx or other sync functions. Callbacks - from timers etc. - are in the calling thread so they are no good to me. I need to protect a block of code as follows, Start timer ------------- Code Block normal exit ------------- Timeout timeout exit The try/catch block is ideal but the timers run in their own threads so I don't catch nothing. Thanks to all! Re: throw and catch Andrew Peace19-Oct-01 13:31 Andrew Peace 19-Oct-01 13:31  AFAIK throwing an exception from a thread will cause the exception to be propogated down the stack of the thread only - if it were to be caught by another thread then the operating being performed by that thread would have to be interrupted etc and it would just be a disaster as well as being unimplentable (practially at least). A better solution is to return an error value from the thread. -- Andrew. Re: throw and catch Joe Moldovan20-Oct-01 17:52 Joe Moldovan 20-Oct-01 17:52  I think you are correct and a thread can't be interrupted. I don't see any great technical difficulty in doing it (that's really what the scheduler does after all) but the system is designed not to do it, so that's that. I looked at APCs but they only work when the thread is sleeping or waiting so that's no good to me either. I need to have functions (node/action functions for a state machine written by others) running by themselves and being timed out in the state engine which I wrote. What do you mean "return an error value from the thread"? Do you mean the value in the terminating "return int" or some other mechanism I don't know about. I know you can get the terminating value when a thread exits is this what you mean? Thanks for your thoughts anyway. Joe M. Re: throw and catch Andrew Peace21-Oct-01 11:14 Andrew Peace 21-Oct-01 11:14  I think you are correct and a thread can't be interrupted. I don't see any great technical difficulty in doing it... Yes, it is easy for threads to be suspended. However, to change the path of execution for a thread is unthinkable - I mean, if your program is carrying out a task and half way through writing to a file the control gets shifted to a code handler you've had it. Yes, I did mena the terminating return int statement. -- Andrew. Automating the build process? Jamie Hale19-Oct-01 9:30 Jamie Hale 19-Oct-01 9:30  Anyone know if it's possible to automate the build process? I have about a dozen projects in one workspace, and I want to be able to say "build all" and have it build each individual project in the right order in the right configuration. Possible? I started to automate with NMAKE and Python, but goddam it would be nice if VC++ did it for me. J Re: Automating the build process? Carlos Antollini19-Oct-01 9:36 Carlos Antollini 19-Oct-01 9:36  Yes, Batch Build. In the menu look for Build and then Batch Build. Is esay to use. Good Luck. Happy Weekend Carlos Antollini. Today is Friday!!! SShhh Bob!!! Re: Automating the build process? Jamie Hale19-Oct-01 9:37 Jamie Hale 19-Oct-01 9:37  That doesn't let me customize the order. J Re: Automating the build process? J Patel19-Oct-01 9:43 J Patel 19-Oct-01 9:43  To customize the order set the dependencies. Project/Dependencies menu pick. HTH Jignesh Re: Automating the build process? Carlos Antollini19-Oct-01 9:53 Carlos Antollini 19-Oct-01 9:53  You can change the order with Project/dependencies but I have a secret... shhh, don't say nothing but sometimes carlos changes the order editing the .dsw file. Is a dangerous practice, but it works. Never change the position of the principal project. Cheers Nice Weekend Carlos Antollini. Today is Friday!!!! SSSShhh Bob!!! Re: Automating the build process? Jamie Hale19-Oct-01 10:10 Jamie Hale 19-Oct-01 10:10  Thanks, but I need a little more flexibility. What I would love to have is a batch build builder. A dialog like the batch build one that would let me pick the projects and the order, and then save that as, say, the "Debug" build. Then I could create another order for the "Release" build. I have a workspace with a dozen projects. Some are COM servers that register themselves during the build. I don't want to have a combination of debug and release servers running, so I want to be able to say "build me the debug version of everthing", or "build me the release/releaseMinDependency version of everything". I started to write a little script that would use nmake or something to do the build, but I was just hoping that something would already exist. Guess not, but thanks for the suggestions. J Re: Automating the build process? Fazlul Kabir19-Oct-01 10:16 Fazlul Kabir 19-Oct-01 10:16  If you need a lot of flexibility, then you can build a macro or an add-in using DevStudio's automation interface. Check this article on MSDN: http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnvs600/html/autobld.asp Hope this helps. // Fazlul Get RadVC today! Play RAD in VC++ http://www.capitolsoft.com Re: Automating the build process? Jamie Hale19-Oct-01 10:57 Jamie Hale 19-Oct-01 10:57  That's what I needed. I hadn't realized that the macro stuff was VBScript. I thought it was just keystrokes and stuff. Thanks so much. J Re: Automating the build process? Tim Deveaux19-Oct-01 10:15 Tim Deveaux 19-Oct-01 10:15  You might also want to look at setting dependencies among the projects (Project menu). If you want to go the command line route, check out "Building a Project from the Command Line" in the MSDN. VC5 required you to export make files and run nmake on em, but in VC6 you can call msdev directly. Kinda cool. Re: Automating the build process? Michael Dunn19-Oct-01 10:23 Michael Dunn 19-Oct-01 10:23  You can run MSDEV with the /MAKE switch to have it build projects in a workspace. See the page "Building a Project from the Command Line" in MSDN for the details. You can also run MSDEV /? to see help on the switches. --Mike-- http://home.inreach.com/mdunn/ "....." -- Silent Bob your with and Regional Settings 19-Oct-01 8:25 19-Oct-01 8:25  I am having trouble with the date and time data types when running my app on a machine in China where the regional settings are different. How do I change the regianl settings to North American style? or is there a better solution? Please help. Re: Regional Settings Carlos Antollini19-Oct-01 8:39 Carlos Antollini 19-Oct-01 8:39  Depends that you need. I build Applications that runs in sevreal countrys with the same problem: For example, In some countrys the people use dd/mm/yyyy but in US the common format is mm/dd/yyyy, I prefer that the people Enter the date, and I get the date, month, and Year. For this I use the COleDateTime class, That permit me make this. The class resolve the problem. When I try to insert the data into a SQL Server, I use the format that I need. In other words I build the format date, from the variables of day, month and year. But you can change the regional settingas, but Is not good for the user. If you are interesting in that please contact me. Carlos Antollini. today is Friday!!!! SSShhh bob!!! Re: Regional Settings Michael Dunn19-Oct-01 10:19 Michael Dunn 19-Oct-01 10:19  Changing the user's regional settings out from under them is a Very Bad Thing. The solution is to not hard-code your program for a particular time or date format. Use GetTimeFormat() and GetDateFormat() when displaying times/dates, and use the date/time picker common control when you need the user to enter a date/time. --Mike-- http://home.inreach.com/mdunn/ "....." -- Silent Bob your with and Re: Regional Settings 19-Oct-01 12:24 19-Oct-01 12:24  thanks for your help.

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