object
<iostream>
std::clog
Standard output stream for logging
Object of class ostream that represents the standard logging stream oriented to narrow characters (of type char). It corresponds, along with cerr, to the C stream stderr.
The standard logging stream is a destination of characters determined by the environment. This destination may be shared by more than one standard object (such as cout or cerr).
As an object of class ostream, characters can be written to it either as formatted data using the insertion operator (operator<<) or as unformatted data, using member functions such as write.
The object is declared in header <iostream> with external linkage and static duration: it lasts the entire duration of the program.
In terms of
static initialization order,
clog is guaranteed to be properly constructed and initialized no later than the first time an object of type
ios_base::Init is constructed.
In terms of
static initialization order,
clog is guaranteed to be properly constructed and initialized no later than the first time an object of type
ios_base::Init is constructed, with the inclusion of
<iostream> counting as at least one initialization of such objects with
static duration.
clog is not tied to any other stream (see ios::tie).
By default, clog is synchronized with stderr (see ios_base::sync_with_stdio).
A program should not mix output operations on clog with output operations on wclog or wcerr (or with other wide-oriented output operations on stderr): Once an output operation has been performed on either, the standard logging stream acquires an orientation (either narrow or wide) that can only be safely changed by calling freopen on stderr.
For more information on the operations supported by clog, see the reference for its type: ostream.
See also
- ostream
- Output Stream (class)
- cout
- Standard output stream (object)
- cerr
- Standard output stream for errors (object)
- cin
- Standard input stream (object)
- wclog
- Standard output stream for logging (wide) (object)