tellp() in file handling with c++ with example
The tellp() function is used with output streams, and returns the current “put” position of the pointer in the stream. It has no parameters and return a value of the member type pos_type, which is an integer data type representing the current position of the put stream pointer.
Syntax:
pos_type tellp();
Return – Current output position indicator on success otherwise return -1.
Example 1 –
CPP
Output –
the current position of pointer is :-1
In the above code the tellp() returns the current position to which it point in a file.
Example 2 –
CPP
// code to add content at particular position // using tellp() #include <fstream> using namespace std; int main() { long position; fstream file; // open the file in read and write mode file.open( "myfile.txt" ); // write content in the file file.write( "this is an apple" , 16); position = file.tellp(); // set position of pointer using seekp file.seekp(position - 7); file.write( " sam" , 4); file.close(); } |
Output –
this is a sample
Here tellp() function returns the position of pointer then using seekp() function the pointer is shift back from n position here it shift 7 position back and then insert the content at that position .