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can someone help me differenciate the functions getch(), getche(), and ungetch() ?
also, I seem to have conflicts when testing this specific code under MSVC 6. It seems that the output happens after the loop terminates.
for(int i=0; i<10; i++)
{
A[i]=getch(); // A is a vector
cout<<A[i];
}
The reason you output appears once the loop ends is becuase your output is buffered. On some machines output is buffered, and must be "flushed" to show the output. This is done by either cout << endl; or fflush(stdout);
The only difference between getch and getche, is that getche will echo the character to the screen, hence the e in the function name.
ungetch will put a char back, so that the next call to getch/getche will return that char that was put back.
The following came from a quick search on google.com, these excerpts come from http://www.delorie.com/djgpp/doc/libc/libc_toc.html
getch
Syntax
#include <conio.h>
int getch(void);
Description
A single character from the predefined standard input handle is read and returned. The input is not buffered. If there is a character pending from ungetch (see section ungetch), it is returned instead. The character is not echoed to the screen. This function doesn't check for special characters like Ctrl-C.
If the standard input handle is connected to the console, any pending output in the stdout and stderr streams is flushed before reading the input, if these streams are connected to the console.
Return Value
The character.
Portability
not ANSI, not POSIX
ungetch
Syntax
#include <conio.h>
int ungetch(int);
Description
Puts a character back, so that section getch will return it instead of actually reading the console.
Return Value
The charater is returned.
Portability
not ANSI, not POSIX
--------------------------------------------------------------------------------
getche
Syntax
#include <conio.h>
int getche(void);
Description
A single character from the predefined standard input handle is read and returned. The input is not buffered. If there is a character pending from ungetch (see section ungetch), it is returned instead. The character is echoed to the screen. This function doesn't check for special characters like Ctrl-C.
If the standard input handle is connected to the console, any pending output in the stdout and stderr streams is flushed before reading the input, if these streams are connected to the console.
Return Value
The character.
Portability
not ANSI, not POSIX