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I'm half asleep today. I ended up writing the following code....
printf("rta %s %s\n", "router""jmd", token);
Even the linux gnu c compiler compiles it OK!
 
I feel like I'm diagonally parked in a parallel universe
Jerry Davis
http://www.astad.org
http://www.jvf.co.uk
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Jeremy Davis wrote:
Even the linux gnu c compiler compiles it OK!
I'm with the compiler. I see nothing wrong with the statement. What do you think is wrong?
"When I was born I was so surprised that I didn't talk for a year and a half." - Gracie Allen
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It's the "string1""string2" bit. It becomes "string1string2". I just never realised you could add strings like that.
My bad then!
I feel like I'm diagonally parked in a parallel universe
Jerry Davis
http://www.astad.org
http://www.jvf.co.uk
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There's really nothing special about it. String constants occupy a spot in memory, and two, contiguous, quoted strings will be right next to each other. Consider the following:
char *pszName = "A really long string here" \
"...and the rest of it here.";results in pszName pointing to "A really long string here...and the rest of it here." in memory.
Make sense?
"When I was born I was so surprised that I didn't talk for a year and a half." - Gracie Allen
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That isn't how it works. The standard specifically says that the strings will be concatenated.
If what you said was true, the strings would have a '\0' between them. Also, there is nothing that says that strings are placed in the EXE in the same order they are found in the source files.
Tim Smith
I'm going to patent thought. I have yet to see any prior art.
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Tim Smith wrote:
The standard specifically says that the strings will be concatenated.
They're not concatenated as there is nothing to concatenate. Concatenation implies two or more strings, whereas the snippet I showed only has one string. The fact that it breaks two lines, or has multiple sets of quotes, is irrelevant.
Tim Smith wrote:
If what you said was true, the strings would have a '\0' between them.
I don't know where you pulled this from. 
Tim Smith wrote:
Also, there is nothing that says that strings are placed in the EXE in the same order they are found in the source files.
Uh, actually there is. While the preprocessor sees two separately quoted strings, once the extra quotes (and backslash) are removed, the compiler sees only one. Therefore, they are in memory in exactly the same way had they been written as one continuous string.
"When I was born I was so surprised that I didn't talk for a year and a half." - Gracie Allen
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Read the C++ standard section 2.13.4.3. It specifically states that:
In translation phase 6 (2.1), adjacent narrow string literals are concatenated and adjacent wide string literals are concatenated. If a narrow string literal token is adjacent to a wide string literal token, the behavior is undefined...
The two strings are concatentated. They way you describe it is totally wrong. It doesn't just ignore the two quotes as also covered in 2.13.4.3. It doesn't just place the two strings after each other in the EXE. Literal string pooling requires that strings be moved around. But that is probably implementation specific but that does not mean it breaks the standard. Please find the section in the standard that says it must do this.
Also, a backslash is not required.
Tim Smith
I'm going to patent thought. I have yet to see any prior art.
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Tim Smith wrote:
Read the C++ standard section 2.13.4.3.
Then I must also consider these examples that accompany the Concatenation section:
Another way to continue a string is to have two or more consecutive strings. Adjacent string literals will be concatenated to produce a single string. The following example demonstrates this:
"hello " "there" // is equivalent to "hello there"
"hello" "there" // is equivalent to "hellothere"
char *third = "Hello " "there"; // stored as "Hello there\0"
Characters in concatenated strings remain distinct. For example, the strings "\xab" and "3" are concatenated to form "\xab3", rather than the single hex character \xab3.
I believe this site also has a mention of how concatenation is implemented.
Tim Smith wrote:
In translation phase 6 (2.1), adjacent narrow string literals are concatenated and adjacent wide string literals are concatenated. If a narrow string literal token is adjacent to a wide string literal token, the behavior is undefined...
My example did not mix wide and narrow literals, but that's not the point here.
Tim Smith wrote:
The two strings are concatentated.
Indeed, but not in the sense of what one typically thinks of with concatenation (e.g., the "+" operator).
Tim Smith wrote:
They way you describe it is totally wrong.
I respectfully disagree, as it makes perfect sense to me and others I've spoken with about it. Perhaps we are saying the same thing two different ways.
Tim Smith wrote:
It doesn't just ignore the two quotes as also covered in 2.13.4.3.
The compiler sees/stores the two concatenated literals as one single literal.
Tim Smith wrote:
It doesn't just place the two strings after each other in the EXE.
If the two concatenated literals were stored separately, how would the compiler know to find the other piece(s)? It's not like there is a pointer at the end of the first one that points to the start of the second one. Look at some of your latest .exe or .dll files and you'll see that string literals are kept together.
Tim Smith wrote:
Literal string pooling requires that strings be moved around.
Of course, but only when they are "pointed to" by different variables. Given a statement such as:
FindThisName(_T("This is someone's very long name"));the string literal is not going to be scattered around in multiple places. If it's moved, it's moved altogether. Now consider:
FindThisName(_T("This is someone's very long name"));
PrintThisAddress(_T("123 W. Evergreen St. Suite 9"));These two string literals are disparate so they will be stored independently of each other. If one is moved, the other might not be, and vice-versa.
Tim Smith wrote:
Also, a backslash is not required.
Of course it's not. I merely used one to show that there were indeed two string literals. Had I used something like:
char *pszName = "A really long string here""...and the rest of it here."; it might not have been immediately obvious that there was more than one literal.
"When I was born I was so surprised that I didn't talk for a year and a half." - Gracie Allen
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Perfectly valid code.
Tim Smith
I'm going to patent thought. I have yet to see any prior art.
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Hi there
Im loading a dll from project1.exe, then start project2.exe by CreateProcess and pass it the Handle of loaded dll as a CommandLine parameter. After this in project2.exe I try to get the dll function's address by caling GetProcAddress with the given handle; But these addresses are NULL!
Where is the problem?
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Are you sure that the handle returned from LoadLibrary() can cross process boundaries?
"When I was born I was so surprised that I didn't talk for a year and a half." - Gracie Allen
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I have a number of CListCtrl objects that are placed at various positions on the screen at random and I need to be able to link items together (like in SQL Server's views when joining tables). I'd like to get any suggestions as to the best way to go about doing this. I'm not asking for any code, just ideas. I don't want to go down one road only to find I'm headed in the completely wrong direction. Thanks in advance; any suggestion is welcome!!
[insert witty comment here]
bdiamond
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I'd go for a 'link-Control' class.
this class maintains all link possebilities. link-control consists of several link-objects.
hope i've been of some assistance.
"If I don't see you in this world, I'll see you in the next one... and don't be late." ~ Jimi Hendrix
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thanks, I was kinda thinking of something along those lines, but I guess I was more talking about the drawing aspect of it. I saw an article here on codeproject that I downloaded that discusses dragging and dropping of listctrl items from one control to the other. Upon the drop completion I would instantiate a new link object. I'm just wondering if there's a certain GDI function I should use to draw the line I want, because it will have to be able to stretch and move when the user scrolls the control or moves the control around. But I do appreciate your help. Thanks!!!
[insert witty comment here]
bdiamond
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Can anyone point me to some good articles about realeasing mfc projects. Ive searched around but im not sure exactly what im looking for.
Ive compiled my proj for release and ive learned how to bundle it with an installer, but i dont know what mfc DLLs (my proj used mfc shared DLL) i need to include and where i need to go about copying them on install.
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KnaveWave wrote:
i dont know what mfc DLLs (my proj used mfc shared DLL)
To find out which DLLs your application uses run the program Depends.exe located:
VS VC6
C:\Program Files\Microsoft Visual Studio\Common\Tools
VS .Net
C:\Program Files\Microsoft Visual Studio .NET 2003\Common7\Tools\Bin
or equivelant directory.
Load the executable into depends and it lists all DLLs that your executable depends on (it does exactly what it says on the tin!). 
KnaveWave wrote:
where i need to go about copying them on install
All dependant DLLs can reside in the working directory for the executable. However most windows installations will already have the appropriate mfc DLLs already installed in the WINDOWS directory or WINDOWS\SYSTEM directory or WINDOWS\SYSTEM32 directoy.
Installers, eg. Wise, InstallShield can/will locate all dependant DLLs for you and add them to the appropriate places within the install package when it is built. These will then be installed as necessary on the client machine.
Ant.
I'm hard, yet soft.
I'm coloured, yet clear.
I'm fruity and sweet.
I'm jelly, what am I? Muse on it further, I shall return! - David Williams (Little Britain)
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That project uses only MFC42.DLL.
You can know what DLL your project uses with Depends utility.
Depending on your application for generating installers, you will need a merge module that incorporates MFC42 with the installation, for example, InstallShield uses MFC42.MSM
Jaime
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I finally made my MFC(GUI) project,but have a problem,after working succesfully once,for second time it doesnt work anymore!(without exiting form GUI).
What can be the problem?Can someone please help?Maybe i need toreinitialize or free something?
Alex
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If ur using some mutex see that u release the mutex. Hope this helps
Dipeka.A.J
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No,no mutex is used..
Ill detail more:
my project(parser XML) i allow user to enter filename of file to be parsed and directories for log files(regularTXT and html) and then allow start parsing(only if user entered file and directory). For translating txt log file to html i have checkbox and if its marked then html-convert function also starts working..
If ots not enough please tell me,also ill post the code tomoroow(although its quite long for posting)
Thank you
Alex
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what doesn't work anymore ?
have you checked the usuals ( memory leak, resource leak, ... ) ?
what are the symptoms ?
Maximilien Lincourt
Your Head A Splode - Strong Bad
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I did check the usuals..
Here some details:
My project(parser XML) i allow user to enter filename of file to be parsed and directories for log files(regularTXT and html) and then allow start parsing(only if user entered file and directory). For translating txt log file to html i have checkbox and if its marked then html-convert function also starts working..
So the problem is after working once,if i want to enter filename e.t.c. once more,it allows entering but it doesnt work..(if i exit from gui interface and start the programm over again it does work(but again just once),but i need it to work without exiting..
If its not enough please tell me,also ill post the code tomoroow(although its quite long for posting)
Thank you
Alex
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did you close the files ? re-initialize variable ? reset the state of the parser ?
as david wrote, did you trace the problem by putting breakpoints to see ( or try to see ) when in the execution path your program stop working properly ?
don't post ALL the code, only the portions that doesn't work ( and after you really "cornered" the bug and/or the offensive function )
Maximilien Lincourt
Your Head A Splode - Strong Bad
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Ok,i'll try to find the problematic place in code exactly,and i'll tell here..
Thank you,
Alex
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Problem solved!!!
It was a small thing actually..Forgot to reset a global variable..
Thank you very much for the help,i'm thankfull
Alex
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