Short notes on 1. Namespaces 2. Exception handling 3. Basic functions of seekg(), seekp(), tellg(), tellp()

1. Namespaces:

Namespaces are a feature in C++ that allow us to group related functions, classes, and variables under a single name. This helps in preventing naming conflicts and organizing code. We can create a namespace using the keyword "namespace" followed by the namespace name and enclosing the contents within curly braces. We can access the contents of a namespace using the scope resolution operator "::". For example:

namespace myNamespace {
   int myFunction() {
      // function code
   }
}
int main() {
   myNamespace::myFunction(); // accessing function from the namespace
   return 0;
}

2. Exception handling:

Exception handling is a mechanism in C++ that allows us to handle errors and unexpected events that occur during program execution. We can use the keywords "try", "catch" and "throw" to implement exception handling. We enclose the code that can generate an exception within the try block. If an exception is thrown, the control is transferred to the catch block, where we can handle the exception. We can use the throw keyword to throw an exception manually. For example:

try {
   // code that may throw an exception
}
catch (exceptionType e) {
   // code to handle the exception
}

3. Basic functions of seekg(), seekp(), tellg(), tellp():

These are file handling functions in C++ that help in positioning the file pointer and getting the current position of the file pointer.

seekg(): This function is used to set the position of the file pointer for input operations. We can use it to move the file pointer to a specific position relative to the beginning, end or current position in the file. For example:

ifstream inFile;
inFile.seekg(10); // move the file pointer to 10th byte from the beginning

seekp(): This function is used to set the position of the file pointer for output operations. We can use it to move the file pointer to a specific position relative to the beginning, end or current position in the file. For example:

ofstream outFile;
outFile.seekp(10); // move the file pointer to 10th byte from the beginning

tellg(): This function is used to get the current position of the file pointer for input operations. It returns the position of the file pointer as an object of type streampos. For example:

ifstream inFile;
streampos position = inFile.tellg(); // get the current position of the file pointer

tellp(): This function is used to get the current position of the file pointer for output operations. It returns the position of the file pointer as an object of type streampos. For example:

ofstream outFile;
streampos position = outFile.tellp(); // get the current position of the file pointer