Store user input to char array

[voice]

I want a user to input text, which can include spaces, tabs etc and store it into char array. User can input longer text than my array size. Smaller code preferred. I need to handle that without overflow. Best way I could find was described at http://www.daniweb.com/software-development/c/tutorials/45806/user-input-strings-and-numbers-c , but upon entering a longer text than my first array size it overflows to second array and doesn't ask for input.

#include <iostream>
#include <stdio.h>
#include <string.h>
using namespace std;

/*
================
MAIN
================
*/
int main( int argc, char ** argv )
{
	char	plaintext[ 8 ];
	char	key[ 10 ];

	cout << "plaintext: ";

	fflush( stdout );
	if ( fgets( plaintext, sizeof plaintext, stdin ) != NULL )
	{
		char *newline = strchr( plaintext, '\n' );
		if ( newline != NULL )
		{
			*newline = '\0';
		}
	}

	cout << "key: ";

	fflush( stdout );
	if ( fgets( key, sizeof key, stdin ) != NULL )
	{
		char *newline = strchr( key, '\n' );
		if ( newline != NULL )
		{
			*newline = '\0';
		}
	}


	cout << "plaintext:<" << plaintext << ">" << endl;
	cout << "key:<" << key << ">" << endl;

	return 0;
}

Here's what I get:

plaintext: salkjflasdjflasdj
key: plaintext:<salkjfl>
key:<asdjflasd>

If you have any link to a tutorial which explains how to handle garbage user input without complicated code, help would be much appreciated.
Sorry for my english.

[tcs]

You have to consume the entire first line before reading in the second one.

BTW:
The following has nothing to do with your problem:
1. You're mixing C stdio with C++ iostreams. This may confuse your IO because both systems use different IO buffers. See http://www.cplusplus.com/reference/ios/ios_base/sync_with_stdio/ for help or better: Only use one of those systems.
2. You want to write a function to read in your character arrays to avoid writing the same code multiple times (line 16-26 and 28-38).

[voice]

Thanks for reply. I added a function to handle input and made the program C-style only.
Thought I don't understand what you mean by this:

You have to consume the entire first line before reading in the second one.

You mean I should copy first array elsewhere before reading second one?

#include <stdio.h>
#include <string.h>

/*
================
input
================
*/
void input( char *text, int size )
{
	fflush( stdout );
	if ( fgets( text, size, stdin ) != NULL )
	{
		char *newline = strchr( text, '\n' );
		if ( newline != NULL )
		{
			*newline = '\0';
		}
		printf("text = \"%s\"\n", text);
	}
}

/*
================
MAIN
================
*/
int main()
{
	char plaintext[ 8 ];
	char key[ 10 ];
	
	input( plaintext, 8 );
	input( key, 10 );
	
	printf( "p: %s\ns: %s\n", plaintext, key );
	
	return 0;
}

[tcs]

static const char EOL = '\n';  // May be defined as '\r' on Macs

/*
================
skipLine
================
*/
void skipLine()
{
    int c;

    while ( (( c = fgetc( stdin )) != EOF ) && ( c != EOL ) )
        ;
}

Add after line 19:

skipLine();


This may work on UNIX and even on WinDOS

[voice]

Thanks a lot, that worked! (I'm on linux btw)

For anyone with same problem, use this function:

#include <stdio.h>
#include <string.h>

void input( char *text, int size )
{
	if ( fgets( text, size + 1, stdin ) != NULL )
	{
		char *newline = strchr( text, '\n' );
		if ( newline != NULL )
		{
			*newline = '\0';
		}
		int c;

		while ( (( c = fgetc( stdin )) != EOF ) && ( c != '\n' ) )
			;
	}
}

Might not be perfect (and most probably isn't) but it works.