159 lines
4.2 KiB
C++
159 lines
4.2 KiB
C++
#include "stlexam.h"
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#pragma hdrstop
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/***************************************************************************
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*
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* ifstream.cpp - basic_ifstream 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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//
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// stdlib/examples/manual/ifstream.cpp
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//
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#include<iostream>
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#include<fstream>
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#include<iomanip>
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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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long l= 20;
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const char *ntbs="Le minot passait la piece a frotter";
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char c;
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char buf[50];
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#ifndef _RWSTD_NO_EXCEPTIONS
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try {
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#endif
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// create a read/write file-stream object on char
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// and attach it to an ifstream object
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ifstream in("ifstream.results.out",ios_base::in | ios_base::out |
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ios_base::trunc);
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if ( !in.is_open() )
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#ifndef _RWSTD_NO_EXCEPTIONS
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throw(ios_base::failure("Open error"));
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#else
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abort();
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#endif
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// tie the ostream object to the ifstream object
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ostream out(in.rdbuf());
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// output ntbs in out
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out << ntbs << endl;
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// seek to the beginning of the file
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in.seekg(0);
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// output each word on a separate line
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while ( in.get(c) )
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{
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if ( ifstream::traits_type::eq(c,' ') )
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cout << endl;
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else
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cout << c;
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}
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cout << endl << endl;
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// move back to the beginning of the file
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in.seekg(0);
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// clear the state flags
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in.clear();
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// does the same thing as the previous code
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// output each word on a separate line
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while ( in >> buf )
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cout << buf << endl;
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cout << endl << endl;
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// output the base info before each integer
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out << showbase;
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ostream::pos_type pos= out.tellp();
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// output l in hex with a field with of 20
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out << hex << setw(20) << l << endl;
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// output l in oct with a field with of 20
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out << oct << setw(20) << l << endl;
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// output l in dec with a field with of 20
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out << dec << setw(20) << l << endl;
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// move back to the beginning of the file
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in.seekg(0);
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// output the all file
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cout << in.rdbuf();
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// clear the flags
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in.clear();
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// seek the input sequence to pos
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in.seekg(pos);
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int a,b,d;
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in.unsetf(ios_base::basefield);
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// read the previous outputted integer
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in >> a >> b >> d;
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// output 3 times 20
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cout << a << endl << b << endl << d << endl;
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#ifndef _RWSTD_NO_EXCEPTIONS
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}
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catch( ios_base::failure var )
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{
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cout << var.what();
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}
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#endif
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return 0;
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}
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