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diff --git a/examples/readlinebuf.h b/examples/readlinebuf.h
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+/*******************************************************************************
+ * $Revision: 1.2 $
+ * $Date: 2001/09/11 06:19:36 $
+ * $Author: vyzo $
+ *
+ * Contents: A streambuf which uses the GNU readline library for line I/O
+ * (c) 2001 by Dimitris Vyzovitis [vyzo@media.mit.edu]
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2  of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ *
+ ******************************************************************************/
+
+#ifndef _READLINEBUF_H_
+#define _READLINEBUF_H_
+
+#include <iostream>
+#include <cstring>
+#include <cassert>
+#include <cstdlib>
+#include <cstdio>
+
+#include <readline/readline.h>
+#include <readline/history.h>
+
+#if (defined __GNUC__) && (__GNUC__ < 3)
+#include <streambuf.h>
+#else
+#include <streambuf>
+using std::streamsize;
+using std::streambuf;
+#endif
+
+class readlinebuf : public streambuf {
+public:
+#if (defined __GNUC__) && (__GNUC__ < 3)
+	typedef char char_type;
+	typedef int int_type;
+	typedef streampos pos_type;
+	typedef streamoff off_type;
+#endif
+	static const int_type eof = EOF; // this is -1
+	static const int_type not_eof = 0;
+
+private:
+	const char* prompt_;
+	bool history_;
+	char* line_;
+	int low_;
+	int high_;
+
+protected:
+		
+	virtual int_type showmanyc() const { return high_ - low_; }
+		
+	virtual streamsize xsgetn( char_type* buf, streamsize n ) {
+		int rd = n > (high_ - low_)? (high_ - low_) : n;
+		memcpy( buf, line_, rd );
+		low_ += rd;
+			
+		if ( rd < n ) {
+			low_ = high_ = 0;
+			free( line_ ); // free( NULL ) is a noop
+			line_ = readline( prompt_ );
+			if ( line_ ) {
+				high_ = strlen( line_ );
+				if ( history_ && high_ ) add_history( line_ );
+				rd += xsgetn( buf + rd, n - rd );
+			}
+		}
+			
+		return rd; 
+	}
+		
+	virtual int_type underflow() {
+		if ( high_ == low_ ) {
+			low_ = high_ = 0;
+			free( line_ ); // free( NULL ) is a noop
+			line_ = readline( prompt_ );
+			if ( line_ ) {
+				high_ = strlen( line_ );
+				if ( history_ && high_ ) add_history( line_ );
+			}
+		}
+			
+		if ( low_ < high_ ) return line_[low_];
+		else return eof;
+	}
+		
+	virtual int_type uflow() {
+		int_type c = underflow();
+		if ( c != eof ) ++low_;
+		return c;
+	}
+		
+	virtual int_type pbackfail( int_type c = eof ) {
+		if ( low_ > 0 )	--low_;
+		else if ( c != eof ) {
+			if ( high_ > 0 ) {
+				char* nl = (char*)realloc( line_, high_ + 1 );
+				if ( nl ) {
+					line_ = (char*)memcpy( nl + 1, line_, high_ );
+					high_ += 1;
+					line_[0] = char( c );
+				} else return eof;
+			} else {
+				assert( !line_ );
+				line_ = (char*)malloc( sizeof( char ) );
+				*line_ = char( c );
+				high_ = 1;
+			}
+		} else return eof;
+
+		return not_eof;
+	}
+ 		
+public:
+	readlinebuf( const char* prompt = NULL, bool history = true ) 
+		: prompt_( prompt ), history_( history ),
+		  line_( NULL ), low_( 0 ), high_( 0 ) {
+		setbuf( 0, 0 );
+	}
+		
+		
+};
+
+#endif