Defines the log domain. See Log Domains.
Libraries should define this so that any messages which they log can be differentiated from messages from other libraries and application code. But be careful not to define it in any public header files.
Log domains must be unique, and it is recommended that they are the
application or library name, optionally followed by a hyphen and a sub-domain
name. For example,
If undefined, it defaults to the default
"") log domain; this is
not advisable, as it cannot be filtered against using the
For example, GTK uses this in its
AM_CPPFLAGS = -DG_LOG_DOMAIN=\"Gtk\"
Applications can choose to leave it as the default
domain. However, defining the domain offers the same advantages as above.