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#include <iostream>
#include <fstream>
#include <string>
using namespace std;
void err(char const *msg); // see earlier example
void err(char const *msg, long value);
void read(istream &index, istream &strings)
{
index.clear();
strings.clear();
// insert the body of the read() function of the earlier example
}
void write(ostream &index, ostream &strings)
{
index.clear();
strings.clear();
// insert the body of the write() function of the earlier example
}
int main()
{
ifstream index_in("index", ios::trunc | ios::in | ios::out);
ifstream strings_in("strings", ios::trunc | ios::in | ios::out);
ostream index_out(index_in.rdbuf());
ostream strings_out(strings_in.rdbuf());
cout << "enter `r <number>' to read line <number> or "
"w <line>' to write a line\n"
"or enter `q' to quit.\n";
while (true)
{
cout << "r <nr>, w <line>, q ? "; // show prompt
string cmd;
cin >> cmd; // read cmd
if (cmd == "q") // process the cmd.
return 0;
if (cmd == "r")
read(index_in, strings_in);
else if (cmd == "w")
write(index_out, strings_out);
else
cout << "Unknown command: " << cmd << '\n';
}
}
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