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// changing position with pubseekpos
#include <iostream> // std::cout, std::streambuf
#include <fstream> // std::fstream
int main () {
std::fstream filestr ("test.txt");
if (filestr) {
std::streambuf* pbuf = filestr.rdbuf();
long size = pbuf->pubseekoff(0,filestr.end); // get size
if (size>20) {
char buffer[11];
// change position to the 10th character
pbuf->pubseekpos(10);
// read 10 characters
pbuf->sgetn (buffer,10);
// append null character to string
buffer[10]=0;
std::cout << buffer << '\n';
}
filestr.close();
}
return 0;
}
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