What are the most common naming conventions in C?

Question

What are the naming conventions commonly use in C? I know there are at least two:

1. GNU / linux / K&R with lower_case_functions
2. ? name ? with UpperC

Answer 1

The most important thing here is consistency. That said, I follow the GTK+ coding convention, which can be summarized as follows:

1. All macros and constants in caps: MAX_BUFFER_SIZE, TRACKING_ID_PREFIX.
2. Struct names and typedef's in camelcase: GtkWidget, TrackingOrder.
3. Functions that operate on structs: classic C style: gtk_widget_show(), tracking_order_process().
4. Pointers: nothing fancy here: GtkWidget *foo, TrackingOrder *bar.
5. Global variables: just don't use global variables. They are evil.
6. Functions that are there, but shouldn't be called directly, or have obscure uses, or whatever: one or more underscores at the beginning: _refrobnicate_data_tables(), _destroy_cache().