143 lines
4 KiB
C++
143 lines
4 KiB
C++
#include "stlexam.h"
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#pragma hdrstop
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/***************************************************************************
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*
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* istream1.cpp - istream example
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* See Class Reference Section
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*
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***************************************************************************
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*
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* (c) Copyright 1994, 1998 Rogue Wave Software, Inc.
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* ALL RIGHTS RESERVED
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*
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* The software and information contained herein are proprietary to, and
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* comprise valuable trade secrets of, Rogue Wave Software, Inc., which
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* intends to preserve as trade secrets such software and information.
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* This software is furnished pursuant to a written license agreement and
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* may be used, copied, transmitted, and stored only in accordance with
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* the terms of such license and with the inclusion of the above copyright
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* notice. This software and information or any other copies thereof may
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* not be provided or otherwise made available to any other person.
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*
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* Notwithstanding any other lease or license that may pertain to, or
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* accompany the delivery of, this computer software and information, the
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* rights of the Government regarding its use, reproduction and disclosure
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* are as set forth in Section 52.227-19 of the FARS Computer
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* Software-Restricted Rights clause.
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*
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* Use, duplication, or disclosure by the Government is subject to
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* restrictions as set forth in subparagraph (c)(1)(ii) of the Rights in
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* Technical Data and Computer Software clause at DFARS 252.227-7013.
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* Contractor/Manufacturer is Rogue Wave Software, Inc.,
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* P.O. Box 2328, Corvallis, Oregon 97339.
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*
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* This computer software and information is distributed with "restricted
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* rights." Use, duplication or disclosure is subject to restrictions as
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* set forth in NASA FAR SUP 18-52.227-79 (April 1985) "Commercial
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* Computer Software-Restricted Rights (April 1985)." If the Clause at
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* 18-52.227-74 "Rights in Data General" is specified in the contract,
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* then the "Alternate III" clause applies.
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*
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**************************************************************************/
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#include<iostream>
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#include<istream>
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#include<fstream>
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int main ( )
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{
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#ifndef _RWSTD_NO_NAMESPACE
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using namespace std;
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#endif
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float f= 3.14159;
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int i= 3;
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char s[200];
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// open a file for read and write operations
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ofstream out("example", ios_base::in | ios_base::out
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| ios_base::trunc);
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// tie the istream object to the ofstream filebuf
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istream in (out.rdbuf());
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// output to the file
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out << "He lifted his head and pondered." << endl;
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out << f << endl;
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out << i << endl;
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// seek to the beginning of the file
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in.seekg(0);
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f = i = 0;
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// read from the file using formatted functions
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in >> s >> f >> i;
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// seek to the beginning of the file
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in.seekg(0,ios_base::beg);
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// output the all file to the standard output
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cout << in.rdbuf();
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// seek to the beginning of the file
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in.seekg(0);
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// read the first line in the file
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// "He lifted his head and pondered."
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in.getline(s,100);
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cout << s << endl;
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// read the second line in the file
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// 3.14159
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in.getline(s,100);
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cout << s << endl;
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// seek to the beginning of the file
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in.seekg(0);
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// read the first line in the file
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// "He lifted his head and pondered."
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in.get(s,100);
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// remove the newline character
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in.ignore();
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cout << s << endl;
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// read the second line in the file
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// 3.14159
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in.get(s,100);
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cout << s << endl;
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// remove the newline character
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in.ignore();
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// store the current file position
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istream::pos_type position = in.tellg();
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out << "replace the int" << endl;
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// move back to the previous saved position
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in.seekg(position);
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// output the remain of the file
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// "replace the int"
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// this is equivalent of
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// cout << in.rdbuf();
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while( !ifstream::traits_type::eq_int_type( in.peek(),
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ifstream::traits_type::eof()) )
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cout << ifstream::traits_type::to_char_type(in.get());
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cout << "\n\n\n" << flush;
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return 0;
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}
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