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So, if that is true, then why would Herb Schildt produce this code in his book(C++ from the Ground Up, 3rd edition):
#include "iostream.h"<br />
#include "cstdio.h"<br />
<br />
<br />
int main()<br />
{<br />
char str[80];<br />
<br />
cout << "Enter a string: ";<br />
gets(str); <br />
cout << "Here is your string: ";<br />
cout << str;<br />
<br />
return 0;<br />
}
It might make sense that the two streams are not synchronized which is the only thing I could think of, however Mr. Schildt has produced otherwise. Possibly a different compilor configuration?
Mr. Schildt shows this in his book:
Enter a string: This is a test<br />
Here is your string: This is a test
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#include "iostream.h"
This is the old way of including the C++ standard headers, which indicates that the book may be a bit outdated. The new headers don't have an extension, e.g.:
#include <iostream><br />
#include <cstdio>
It is up to the iostreams implementation to decide how to handle buffering, and some older implementations may have synchronization between iostreams and stdio turned on by default.
- Mike
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Okay, however it is due to my mistake that the includes are listed as so. I had actually changed the <iostream> to "iostream.h" because the web forum didn't display that till I figured out that feature.
Which leads me to my main point, which is how am I supposed to learn this book of the stuff doesn't compile. I paid alot of money for this book, and I don't think it's old either.
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I haven't read any of the C++ books by Herb Schildt, but I've heard both good and bad things about them. The edition you mentioned was published in March 2003, which is indeed fairly recent, so I would expect it to follow more modern conventions.
The code snippet you posted earlier should work fine (it compiles fine in VC6 for me, with the using namespace std; line and the includes changed to their modern versions) since all the input is coming from one type of stream and all the output is going to another type of stream. The problem arises when you read in data from two different types of streams or write data to two different types of streams.
Stylistically, I would argue that mixing cstdio and iostream is generally a bad idea, even in a case like this. Also, gets() is inherently unsafe, since the program would break if a line longer than 80 characters was entered. Hopefully, this was noted in the book. If not... eep. 
shawnsch wrote:
how am I supposed to learn this book of the stuff doesn't compile.
What was the compiler error? I'm curious, since, as I mentioned, I just tried it in VC6 and it compiled and ran. Here is the version I tried:
#include <iostream><br />
#include <cstdio><br />
<br />
using namespace std;<br />
<br />
int main()<br />
{<br />
char str[80];<br />
<br />
cout << "Enter a string: ";<br />
gets(str); <br />
cout << "Here is your string: ";<br />
cout << str;<br />
<br />
return 0;<br />
}
- Mike
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Hello,
I have a question that should be easy but I'm having a major brain fart..
How would one copy a char/buffer into a structure? I know this isn't correct but it may help you understand what im trying to do...
memcpy((char FAR*)&sMyStruct, pBuff, sizeof(pBuff));
Whoever said nothing's impossible never tried slamming a revolving door!
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Assuming pBuff is a pointer to an array of bytes, this won't work because sizeof(pBuff) will always return 4 (the size of the pointer). You need to pass in the actual number of bytes to copy instead.
Dave
http://www.cloudsofheaven.org
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That was it, thanks..
Rob
Whoever said nothing's impossible never tried slamming a revolving door!
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I'm trying to place a value in HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run so that my app starts up when windows starts up, as a background app. I've implemented DLLRegisterServer so that it is invoked when the setup.exe runs (I've set the .exe to self-register under InstallShield). In DLLSelfRegister, I need the path to the .exe so that the value in the registry is set properly and the .exe runs from that path. I use GetModuleFileName to get the path of the app, but when regsvr32 myApp.exe is run, the app is not instantiated yet.
I used MFC to create a dialog based app
Here's a code snipet:
CSysTrayDemoApp theApp; //MFC generated
...
//Implement this funciton so that regsvr32 can invoke it to register exe.
STDAPI DllRegisterServer()
{
char path[MAX_PATH];
DWORD pathLen = sizeof(fileName);
__asm int 3;
GetModuleFileName(theApp.m_hInstance, path, pathLen);
...
theApp.m_hInstance is not instantiated and thus I can't get the path name.
Does anyone have experience in registering an app/is there a better way of doing this?
Thanks,
Raymond
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Try passing in NULL as the HINSTANCE for GetModuleFileName() - that means it retrieves the name of the current module. The most likely reason for theApp.m_hInstance not being initialised is that DllRegisterServer normally does not need to call DllMain(), so your normal application initialisation has not occurred.
Dave
http://www.cloudsofheaven.org
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As you are registering EXE -- this is outproc server.
Why would you need regsvr32 for that (it's used for inproc servers)?
Instead, you should start your outproc server with /REGSERVER and process it properly in yours InitInstance (or whatever)...
"...Ability to type is not enough to become a Programmer. Unless you type in VB. But then again you have to type really fast..."
Me
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Is there a way to trap a mouse click on your taskbar window button.
My application does not have the title bar. So am facing two problems.
1. I cannot restore my application by clicking on the taskbar window button, if it is minimized.
2. On Windows 2000 if I choose Minimize All, my app is not minimized along with the other apps.
Help wanted badly!!!
Thanks,
Blade
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I would like to execute an EXE from memory (instead of disk). Is this practical? If so, does anyone have any hints or suggestions as to how it can be accomplished?
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Yes. Search MSDN and the Net for the PE file format.
Five birds are sitting on a fence.
Three of them decide to fly off.
How many are left?
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I undoubtably have horrible MSDN searching skills, however the most I gleaned from a massive article with way too much information I'm not interested in was:
"When PE files are loaded into memory via the Windows loader"... bla bla bla.
I'm just wondering if there is some relatively easy way (in the Win32/C++ world) to launch a PE from memory (instead of disk)?
From disk we have lots of API's... WinExec, CreateProcess, ShellExecute, etc.
What's the basic technique for launching from memory? Is assembly required? 
I'm just basically looking for a tidbit of information to give me a headstart -- before having to comprehend all of the information about PE files and apparently the Windows loader and such.
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Hi!
I need to be able to launch a viewer for a given file from my application (Win32/MFC/C++). Ideally I'd like to present the user with choices similar to the "Open With..." feature of the explorer shell.
I tried SHGetFileInfo but it keeps returning 0 for the flag SHGFI_TYPENAME (failure).
So I assume there's two part in my quest:
1- Find the type (mime type?) a given extension (I don't necessarily have the file created yet -- i.e. I'd like the user to be able to choose before creating the file)
2- Find a list of suitable applications (path, "user friendly" name) that can open that mime type.
I seems like I could just go and fish the info from the registry, but would that work on any windows version?
Regards
R/
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ralfoide wrote:
I could just go and fish the info from the registry
seems like the only way.
Hush,hush...
thought I heard you call my name now.
Kula Shaker.
Amit Dey
Latest articles at CP -
Writing Word addins
Office addin
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Hi everyone,
Just a quick question. Is there a way to display binary when formatting a string? I know %d is decimal, %X is hex....is there one that even exists for binary?
Jimmy
Just cause I am 15, doesn't mean I'm dumb! (I'll really be 4 on Feb. 29...the year 2004)
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There isn't a ready-made format specifier like %b that will format an integer in binary. You'll have to brew your own by walking the bits.
/ravi
Let's put "civil" back in "civilization"
Home | Articles | Freeware | Music
ravib@ravib.com
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NewHSKid wrote:
...is there one that even exists for binary?
No, you'll need to roll your own.
Five birds are sitting on a fence.
Three of them decide to fly off.
How many are left?
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There are several ways. Here are a few.
The example below will display the binary representation for the decimal 100. In addition to '#including' <bitset>, you'll also have to '#include' <limits>
cout<<"\n 100: " <<bitset<numeric_limits<unsigned int>::digits>(100)<<endl;
the="" example="" below="" will="" also="" display="" the="" binary="" configuration="" for="" decimal="" 85.
cout<<"\n="" 85:="" "="" <<bitset<8="">::bitset(85) <<endl;
there are="" some="" subtle="" differences="" between="" the="" first="" example="" and="" second,="" but="" biggest="" is="" that="" in="" second="" you="" interested="" only="" having="" eight="" bits="" to="" represent="" value,="" whereas="" you'll="" get="" 32="" value.="" iow,="" can="" restrict="" number="" of="" want="" have="" representing="" value="" you're="" displaying.
here's="" one="" for="" letters.="" it="" will="" show="" binary="" representation="" letter="" 'a'="" using="" 8="" bits.
cout<<"\n="" \"a\":="" "="" <<bitset<8="">('A') <<endl;
lastly, here's="" one="" to="" show="" a="" string="" of="" letters="" (e.g.="" "abcd").
bitset<32=""> Ltrs = bitset<numeric_limits<unsigned int>::digits>('ABCD');
cout<<"\n \"ABCD\": " <
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Hi!
How can i determine that the pointer is pointing to a valid memory address??
e.g:
consider
class CTest
{
public:
void Release()
{
delete this;
}
};
CTest *pTest = NULL
pTest = new CTest();
pTest->Release();
If you look at the last statement i.e pTest->Release();, the memory poionted by pTest is deleted, but pTest still contains some value. I want to determine whether the value in pTest is a valid address or not ? How can i do so ?
N.B, I've read somewhere that in MFC the is a function something like AfxIsValidAddress(), but i would prefer a non-mfc solution
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You can use one of several Win32 APIs to check the validity of a pointer: IsBadCodePtr(), IsBadReadPtr(), IsBadStringPtr() and IsBadWritePtr() as well as the Huge analogs.
/ravi
Let's put "civil" back in "civilization"
Home | Articles | Freeware | Music
ravib@ravib.com
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Unfortunately, AfxIsValidAddress() and related functions like IsBadReadPtr() don't tell you if the pointer has been freed or not. They know if the address can be read from and/or written to. You'll just need to get into the habit of assigning NULL to the pointer after delete has been called.
Five birds are sitting on a fence.
Three of them decide to fly off.
How many are left?
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