Set the Include Directory Path for the MPLAB® XC32 Compiler
The Include Directory paths are used by the C compiler to find files referenced through #include directives. This is the preferred method of referencing include files that are not at the root of your project directory, as opposed to using relative paths in code: #include "subdirectory/filename.h").
Open the project properties window
Either right-click on the top node of the project in the Project window and select Properties from the pop-up window, or from the File menu, select Project Properties (ProjectName).
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Select the compiler options
Select xc32-gcc from the Categories list on the left side of the Project Properties window. (GCC stands for GNU C Compiler)
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Preprocessing and messages settings
From the Option categories drop down menu select Preprocessing and messages
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Add include directory path(s)
Click on the box next to the Include directories item to open the C include directories dialog box.
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Create a new path
Click on the Browse button to select the desired directory.
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