Pooja

• Aug 26th, 2013

 

There are 6 main types of file opening mode:

1) "r". Open file for reading and file must exist;

2) "w" Open file for writing. If file does not exist it is created or if life already exist its content is erased.

3) "a" Open file for appending. It adds all information at the end of the file leaving old data untouched. If file does not exist it is created.

4) "r+" Open file for reading and writing and file must exist.

5) "w+" Open file for writing and reading. If file does not exist it is created or if life already exist its content is erased.

6) "a+" Open file for appending and reading. Again all new data is written at the end of the file old data leaving untouched. If file does not exist it is created. (You can read old data by moving pointer in file using fseek or rewind functions from stdio.h. But all writing operations will be done at the end of the file no matter how you change pointer)