Error c4996 getch

How to solve C++ Error C4996 ‘getch’: The POSIX name for this item is deprecated. Instead, use the ISO C and C++ conformant name: _getch

Carlos Delgado

Learn why this error appears in your C++ code and how to solve it.

For newbies in C++ using modern tools may become a big headache, specially when the VS version of your school is pretty old and you have the latest version of VS at home. One of the most known exercises for students, is the famous hello world in this language. Playing with a console application, the exercise is simple, print «hello world» and keep the console open to see the printed message. According to the programming style of your teacher you may receive an example snippet using cout:

Or using printf to print the text in the console:

Both scripts are totally valid and they use the getch method to keep the console open. They should work normally in the compilers of the school where VS is always outdated, however, if you use a modern compiler to compile any of the previous examples (using latest version of Visual Studio), you will face the exception. The problem is that the getch method is a non-standard function, and MS compilers have traditionally offered those under two names, but Microsoft decided to define the name without underscore deprecated, because those names are reserved for the programmer.

Solution

The most simple workaround for this issue is to use the _getch method with an underscore as prefix:

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C error c4996 getch

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Question

I have been writing some code to a program that I wanted, which deals with multi-menu’s and sets in creating rooms customers

and deleting add and modifying on the fly. My problem persists in the function on the getch() format in C++. In which I keep getting errors. Here is some of my code too assist you in seeing my dilemma.

c:usersmrrosedocumentsvisual studio 2008projectshardmotelhardmotelhardmotel.cpp(125) : warning C4996: ‘getch’: The POSIX name for this item is deprecated. Instead, use the ISO C++ conformant name: _getch. See online help for details.

Here is the sample coding I have:

«ntttPress any key to continue. » ;

Any Suggestions are welcome.. Thanks to all.

Answers

If I were you I would read the error, specifically the «warning C4996: ‘getch’: The POSIX name for this item is deprecated. Instead, use the ISO C++ conformant name: _getch. See online help for details.» and then I’d change the function name of getch to the ISO C++ conformant name _getch(); making your code:

Hope this helps!

You simply can do it by using do .. while<> loop .Enter you choice read it poerform the req operation based on input and once you are done you can ask for what else he want to do etc. Second instead of getch() you simply can use std::cin.get();

If you intended this block of code to present the error message to the use and then allow him time to read and think about it before continuing, you will run into another problem. The cin or other input method into which the user entered the wrong value will often leave residual data in the input buffer. (If the input was well formed, this residual data is just the ‘n’ character that resulted from the Enter key being pressed.) Calling getch or _getch will grab that residual character immediately and your program will continue to the next statement without waiting at all.

By the way, the diagnostic message you quoted is labeled a warning, not an error. The fact that Microsoft deprecates a function does not mean the function will not work as intended. You can ignore the warning or use #pragma to suppress it if you so choose.

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warning C4996: ‘getch’: The POSIX name for this item is deprecated.

Hello
I have no idea what does this error message means.
the error message is related to the switch statement in function paintGame.
It is not the complete code I just put the codes that might help to understand it.

any suggestion would be appreciated.
Thanks

I can’t see how it’s realted to the switch statement. You don’t call getch() there.

The problem is that getch() is a non-standard function, and MS compilers have traditionally offered those under two names — once simply as they are, once with a leading underscore (_getch()), as befits a standard library extension. Apparently, the new compilers warn that the versions without the leading underscore (misleadingly called «POSIX names» — that’s because the same warning also applies to the POSIX compatibility functions the compiler offers) are deprecated, i.e. they might go away in a future version of the compiler.

The solution is to use _getch() instead of getch(), or better yet, use something else entirely.

All the buzzt!
CornedBee

«There is not now, nor has there ever been, nor will there ever be, any programming language in which it is the least bit difficult to write bad code.»
— Flon’s Law

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C error c4996 getch

For an assignment, I’m supposed to create a class called piano and then use the methods:

1-) LoadNotes. This function takes a string as a parameter, the parameter is a file name that contains notes. The notes are already shown in the code you’re given. Load Notes should read the notes into an array of characters (or strings)

2-) PlayNotes. This function simply plays the notes that were loaded by LoadNotes.

However, whenever I try to run the code in visual studio it stops working at line 18. Are there any hints you could give me or any easy fixes to make my code run? Any help would be greatly appreciated.

please use code tags for code. soon people will stop answering if you do not.

a class creates a new type.
where is main()?

you should have a main:

Which line is 18? If you would use code tags in the post, then it would be easy to see. Read https://www.cplusplus.com/articles/jEywvCM9/

Your code in tags and with some indentation:

Is the line 18 this: void LoadNotes(string mynotes.txt) ?

What exactly does the visual studio give as error message?

Note:

The general rules for naming variables are:
* Names can contain letters, digits and underscores
* Names must begin with a letter or an underscore (_)
* Names are case sensitive (myVar and myvar are different variables)
* Names cannot contain whitespaces or special characters like !, #, %, etc.
* Reserved words (like C++ keywords, such as int) cannot be used as names

Your name for a variable, the mynotes.txt , violates one of them. Dot is not a letter, digit, nor underscore.

Variable names cannot have ‘.’s in them. String literals should have «» around them.

The return statement at the end of a void function is not necessary.

I took into account what y’all had to say and made some changes, but I still can’t get it to run. Whenever I try, I get the following error messages:

Error (active) E0065 expected a ‘;’ ConsoleApplication2 16

Error (active) E0415 no suitable constructor exists to convert from «const char [1]» to «Piano» ConsoleApplication2 17

Error (active) E0169 expected a declaration ConsoleApplication2 18

Error (active) E0070 incomplete type is not allowed ConsoleApplication2 23

Error (active) E0020 identifier «filename» is undefined ConsoleApplication2 23

Error (active) E0135 class «Piano» has no member «LoadNotes» ConsoleApplication2 28

Error C2143 syntax error: missing ‘;’ before ‘>’ ConsoleApplication2 16

Error C2440 ‘initializing’: cannot convert from ‘const char [1]’ to ‘Piano’ ConsoleApplication2 17

Error C2079 ‘input_file’ uses undefined class ConsoleApplication2 23

Error C2065 ‘filename’: undeclared identifier ConsoleApplication2 23

Error C2039 ‘LoadNotes’: is not a member of ‘Piano’ ConsoleApplication2 28

Error C2731 ‘main’: function cannot be overloaded ConsoleApplication2 32

Error C4996 ‘getch’: The POSIX name for this item is deprecated. Instead, use the ISO C and C++ conformant name: _getch. See online help for details. ConsoleApplication2 36

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C error c4996 getch

Can you help me remove these errors? I try to start to build program, one of my first tries, to capture content of window. I took this script which originally should capture screen and try to remake it.

update
cpp: pls see the actual code and reports bellow

I had forgotten there must me main function. I removed the code for this one, looks better:

EDIT
It still generates errors:

—— Rebuild All started: Project: capture2, Configuration: Debug Win32 ——
stdafx.cpp
capture.cpp
s:tempc++algoritmycapture2capturecapture.cpp(13): warning C4996: ‘getch’: The POSIX name for this item is deprecated. Instead, use the ISO C++ conformant name: _getch. See online help for details.
p:programyprogramováníc++visual studio 10.0vcincludeconio.h(128) : see declaration of ‘getch’
s:tempc++algoritmycapture2capturecapture.cpp(28): error C2440: ‘initializing’ : cannot convert from ‘HGDIOBJ’ to ‘HBITMAP’
Conversion from ‘void*’ to pointer to non-‘void’ requires an explicit cast
s:tempc++algoritmycapture2capturecapture.cpp(30): error C2065: ‘width’ : undeclared identifier
s:tempc++algoritmycapture2capturecapture.cpp(30): error C2065: ‘height’ : undeclared identifier
s:tempc++algoritmycapture2capturecapture.cpp(31): error C2440: ‘=’ : cannot convert from ‘HGDIOBJ’ to ‘HBITMAP’
Conversion from ‘void*’ to pointer to non-‘void’ requires an explicit cast
Generating Code.
========== Rebuild All: 0 succeeded, 1 failed, 0 skipped ==========

I have finally found good script which after correction works. I remake it now to capture from window, but here I have a question. I try to use GdipCreateBitmapFromHBITMAP()

but result is error:

error C3861: ‘GdipCreateBitmapFromHBITMAP’: identifier not found
I even try to include
But still the same. How to fix?

Can you help to solve unresolved external problem in program using GDI+ Flat API?

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int	c;

	dltXY = XY_DLT; dltAB = AB_DLT;

	flag_move = 0;
	c = getch();
	c = toupper(c);
	if (c == 'Q')
		return 1;

struct sockaddr_in sa

CodeProject,
20 Bay Street, 11th Floor Toronto, Ontario, Canada M5J 2N8
+1 (416) 849-8900

Class Will Not Run

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#include <cstdlib>
#include <iostream>
#include <conio.h>
#include <windows.h>
using namespace std;

class Piano 
{
//Member variables
private:
string notes;
//Member functions
 public:
//default constructor
Piano() {
notes = "";
}
void LoadNotes(string mynotes.txt)
{
char note;
ifstream input_file(mynotes.txt);
return;

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int main()
{
  //and it should contain your variable:
   Piano p;
   //and you can use that:
   p.LoadNotes("file");
}

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#include <cstdlib>
#include <iostream>
#include <conio.h>
#include <windows.h>
using namespace std;

class Piano {
    //Member variables
private:
    string notes;
    //Member functions
public:
    //default constructor
    Piano() {
        notes = "";
    }
    //Load notes from file
    void LoadNotes(string mynotes.txt)
    {
        char note;
        ifstream input_file(mynotes.txt);
        return;
    }

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void LoadNotes(string filename)
{
    ifstream input_file(filename);
    // ...
}

// ...

int main()
{
   Piano p; // borrowing from jonnin's post
   p.LoadNotes("mynotes.txt");
}

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#include <cstdlib>
#include <iostream>
#include <conio.h>
#include <windows.h>
using namespace std;

class Piano 
{
    //Member variables
private:
    string notes;
    //Member functions
public:
    //default constructor
    Piano();
}
        notes = "";
        {
            //Load notes from file
            void LoadNotes(string filename)
        }
        char note;
        ifstream input_file(filename);

int main()
{
    Piano p;
   p.LoadNotes("filenmae");
}

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// Example program
#include <iostream>
#include <fstream>
#include <string>

using namespace std;

class Piano 
{
private:
    string notes;

public:
    void LoadNotes(string filename)
    {
        //Load notes from file
        ifstream input_file(filename);
        
        if (!input_file)
        {
            cout << "Error reading filen";
            return;
        }

        //
        // ... read from input_file here ...
        //
    }
};

int main()
{
    Piano p;
    p.LoadNotes("filename.txt");
}

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#include <cstdlib>
#include <iostream>
#include <conio.h>
#include <windows.h>
using namespace std;

class Piano 
{
    //Member variables
private:
    string notes;
    //Member functions
public:
    //default constructor
    Piano();
} // E0065 expected a ';'
// The definition of class must end with ;
// This closing brace matches the opening brace on line 8 

Error C2731 'main': function cannot be overloaded ConsoleApplication2 32

Error C4996 'getch': The POSIX name for this item is deprecated. Instead, use the ISO C and C++ conformant name: _getch. See online help for details. ConsoleApplication2 36

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class Piano
{
private:
    string notes;

public:
    void LoadNotes(string filename)
    {
        //Load notes from file
        ifstream input_file(filename);

        if (!input_file)
        {
            cout << "Error reading filen";
            return;
        }

        //
        // ... read from input_file here ...
        //
    }
};

int main()
{
    Piano p;
    p.LoadNotes("filename");
}

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#include <cstdlib>
#include <iostream>
#include <conio.h>
#include <windows.h>
using namespace std;

int main(int argc, char *argv[])
{
  while(true){
              cout<<"Input note: ";
              char note = getch();
              
              
              //do re mi fa sol la si do re mi fa sol
              if(note == 'a'){
                      Beep(261,100);
                      }
              if(note == 's'){
                      Beep(293,100);
                      }
              if(note == 'd'){
                      Beep(329,100);
                      }
              if(note == 'f'){
                      Beep(349,100);
                      }
              if(note == 'g'){
                      Beep(392,100);
                      }
              if(note == 'h'){
                      Beep(440,100);
                      }
              if(note == 'j'){
                      Beep(493,100);
                      }                      
              if(note == 'k'){
                      Beep(523,100);
                      }                      
              if(note == 'l'){
                      Beep(587,100);
                      }
              if(note == ';'){
                      Beep(659,100);
                      }  
              if(note == '''){
                      Beep(698,100);
                      } 
               if(note == '\'){
                      Beep(784,100);
                      } 
                      
               //rebemol mibemol solbemol labemol sibemol rebemol mibemol solbemol
               if(note == 'w'){
                      Beep(277,100);
                      } 
                      if(note == 'e'){
                      Beep(311,100);
                      }
                      if(note == 't'){
                      Beep(370,100);
                      }
                      if(note == 'y'){
                      Beep(415,100);
                      }
                      if(note == 'u'){
                      Beep(466,100);
                      }
                      if(note == 'o'){
                      Beep(554,100);
                      }
                      if(note == 'p'){
                      Beep(622,100);
                      }
                      if(note == ']'){
                      Beep(740,100);
                      }     
                      
            system("cls");          
}  
    
    return EXIT_SUCCESS;
} 

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#include <cstdlib>   // EXIT_SUCCESS, system
#include <iostream>  // std::cout
#include <string>    // std::string
#include <fstream    // std::ifstream
#include <conio.h>   // getch or _getch
#include <windows.h> // Beep 

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#include <cstdlib>
#include <iostream>
#include <conio.h>
#include <windows.h>
#include<fstream>
using namespace std;
//Create a class Piano
class Piano {
	//Member variables
private:
	string notes;
	//Member functions
public:
	//default constructor
	Piano() {
		notes = "";
	}
	//Load notes from file
	void LoadNotes(string filename) {
		char note;
		ifstream input_file(filename);
		if (!input_file.is_open()) {
			cerr << "Could not open the file - '"
				<< filename << "'" << endl;
			return;
		}
		while (input_file.get(note)) {
			notes += note;
		}
		input_file.close();
	}
	//Play notes
	void PlayNotes() {
		for (const auto& note : notes) {
			if (note == 'a') {
				Beep(261, 100);
			}
			if (note == 's') {
				Beep(293, 100);
			}
			if (note == 'd') {
				Beep(329, 100);
			}
			if (note == 'f') {
				Beep(349, 100);
			}
			if (note == 'g') {
				Beep(392, 100);
			}
			if (note == 'h') {
				Beep(440, 100);
			}
			if (note == 'j') {
				Beep(493, 100);
			}
			if (note == 'k') {
				Beep(523, 100);
			}
			if (note == 'l') {
				Beep(587, 100);
			}
			if (note == ';') {
				Beep(659, 100);
			}
			if (note == ''') {
				Beep(698, 100);
			}
			if (note == '\') {
				Beep(784, 100);
			}
			//rebemol mibemol solbemol labemol sibemol rebemol mibemol solbemol
			if (note == 'w') {
				Beep(277, 100);
			}
			if (note == 'e') {
				Beep(311, 100);
			}
			if (note == 't') {
				Beep(370, 100);
			}
			if (note == 'y') {
				Beep(415, 100);
			}
			if (note == 'u') {
				Beep(466, 100);
			}
			if (note == 'o') {
				Beep(554, 100);
			}
			if (note == 'p') {
				Beep(622, 100);
			}
			if (note == ']') {
				Beep(740, 100);
			}
		}
	}
};
int main(int argc, char* argv[])
{
	//Create object
	Piano mypiano;
	//Load notes from file
	mypiano.LoadNotes("mynotes.txt");
	//Play
	mypiano.PlayNotes();
	return EXIT_SUCCESS;
}

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warning C4996: ‘getch’: The POSIX name for this item is deprecated. Instead, use the ISO C++ conformant name: _getch.

This compiler warning indicates that there is a reference to the ‘getch()’ function in the code. The compiler is suggesting that the code be updated to use the ‘_getch()’ function instead.

Generally, this error will occur in a Microsoft development environment. Way back, a long time ago, Microsoft introduced the ‘getch()’ [and ‘getche()’] functions. These functions would wait for the user to press a key, and then retun that key character back to the caller. The ‘getch()’ function would not ‘echo’ the key back to the (DOS or early Windows) screen, while ‘getche()’ would echo the key pressed to the screen.

The ‘getch()’ and ‘getche()’ functions were not adopted by other environments, such as *nix. Eventually, Microsoft elected to rename the functions with a leading underscore to help identify their proprietary (Microsoft) nature.

By the look of the error message, I assume that the ‘_getch()’ function has been adopted by the «ISO C++» standard. (However, I don’t do C++ as it is an abomination to many C programmers such as myself).

Note: The *nix ‘curses’ library also sports a getch() which is somewhat similar to the old Microsoft function.

The compiler warning noted in the question is just that; a warning. Most likely, code will still compile and run (in a Microsoft environment).