C Naming Conventions

Overview

This page explains my preferred naming convention style for C code.

Variables

All local variables (variables within a function) begin with a lower-case letter and use camel-case, including function pointers. Only the first letter in an acronym is capitalised, e.g.

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void MyFunction() {
    uint8_t activeGpsAnt;
}

All file-level and global variable use the same syntax except with an underscore in front of them.

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uint8_t _activeGpsAnt;

void MyFunction() {
    // code here...
}

Functions

Functions start with the file/module name, an underscore, and then a description. All functions use camel-case and begin with a capital letter. For example, a function in a file called Gps.c would look like…

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void Gps_GetLocation();

Typedefs

Typedefs aways end in _t. The helps the reader instantly distinguish a data type from anything else, and also serves to distinguish user defined data types (e.g. uint8_t, myType_t) from system data types (e.g. char, double, int).

Acronyms

When it comes to capitalisation rules, acronyms are treated if they were a standard word, and only the first letter of the acronym is capitalised. For example, if you had a GPS variable, it would be named:

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bool gpsEnabled = true;

Similarly, for functions:

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Gps_SetEnabled();