c_g_signal_connect_data

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
__gshared extern (C)
gulong function(void* instanc, const(char)* detailedSignal, GCallback cHandler, void* data, GClosureNotify destroyData, GConnectFlags connectFlags) c_g_signal_connect_data;

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