/*************************************************************************** * * ifstream.cpp - basic_ifstream example. * * $Id: ifstream.cpp 648752 2008-04-16 17:01:56Z faridz $ * *************************************************************************** * * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed * with this work for additional information regarding copyright * ownership. The ASF licenses this file to you under the Apache * License, Version 2.0 (the "License"); you may not use this file * except in compliance with the License. You may obtain a copy of * the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or * implied. See the License for the specific language governing * permissions and limitations under the License. * * Copyright 1994-2006 Rogue Wave Software. * **************************************************************************/ #include // for fstream #include // for setw #include // for dec, hex, oct, right, showbase #include // for cerr, cout #include // for isspace() #include int main ( ) { const char ntbs[] = "Le minot passait la piece a frotter."; try { // create a read/write file-stream object std::ifstream in ("ifstream.results.out", std::ios::in | std::ios::out | std::ios::trunc); if (!in.is_open ()) throw (std::ios::failure ("open error")); // associate the ostream object's buffer with the ifstream object std::ostream out (in.rdbuf ()); // output ntbs in out out << ntbs << '\n'; // seek to the beginning of the file in.seekg (0); char c; // output each space-separated word on a separate line while (in.get (c)) { if ((std::isspace)(c, in.getloc ())) std::cout << '\n'; else std::cout << c; } std::cout << '\n'; // clear stream state, failbit | eofbit set by last call to get () in.clear (); // move back to the beginning of the file in.seekg (0); char buf [40]; // guard against buffer overflow in.width (sizeof buf); // set right justification std::cout << std::right; // does the same thing as the previous code // output each word on a separate line in a field of width 10 while (in >> buf) { std::cout.width (10); std::cout << buf << '\n'; } std::cout << '\n'; // clear the stream state in.clear (); // output the base info before each integer out << std::showbase; std::ostream::pos_type pos= out.tellp (); const long x = 10; // output x in hex with a field with of 10 out << std::hex << std::setw (10) << x << '\n'; // output x in oct with a field with of 10 out << std::oct << std::setw (10) << x << '\n'; // output x in dec with a field with of 10 out << std::dec << std::setw (10) << x << '\n'; // move back to the beginning of the file in.seekg (0); // output the entire file std::cout << in.rdbuf () << '\n'; // clear the stream state in.clear (); // seek the input sequence to pos in.seekg (pos); long a = 0; long b = 0; long d = 0; in.unsetf (std::ios::basefield); // read the previous outputted integer in >> a >> b >> d; // output 3 times 10 std::cout << a << '\n' << b << '\n' << d << '\n'; } catch (std::ios::failure e) { std::cerr << e.what () << '\n'; } return 0; }