ios_base Class
The class describes the storage and member functions common to both input and output streams that do not depend on the template parameters. (The template class basic_ios describes what is common and is dependent on template parameters.)
An object of class ios_base stores formatting information, which consists of:
Format flags in an object of type fmtflags.
An exception mask in an object of type iostate.
A field width in an object of type int*.*
A display precision in an object of type int.
A locale object in an object of type locale.
Two extensible arrays, with elements of type long and void pointer.
An object of class ios_base also stores stream state information, in an object of type iostate, and a callback stack.
For a list of all members of this type, see ios_base Members.
Requirements
Header: <ios>
Namespace: std
See Also
Reference
Thread Safety in the Standard C++ Library