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

There could be many, mainly IDEs dictate some trends and C++ conventions are also pushing. For C commonly:

• UNDERSCORED_UPPER_CASE (macro definitions, constants, enum members)
• underscored_lower_case (variables, functions)
• CamelCase (custom types: structs, enums, unions)
• uncappedCamelCase (oppa Java style)
• UnderScored_CamelCase (variables, functions under kind of namespaces)

Hungarian notation for globals are fine but not for types. And even for trivial names, please use at least two characters.