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File Types

Table of contents


1. Introduction

2. File types

   2.1 Text files

   2.2 Special files

   2.3 Other files and directories

   2.4 Settings files


1. Introduction

In this article U++ related files and files types will be discussed.

2. File types

2.1 Text files

Text files are widely supported by our integrated environment TheIDE. Many of them are used in the daily development process of U++ applications.


.cpp, .cc, .cxx, .c, .m, .mm

Files with these extensions are recognized as source files by TheIDE C++ builders.

.h, .hpp

Header files. C++ builders provide automatic header dependency tests. U++ packages tend to use h instead of hpp in case that file contains template function definitions.


This file type is recognized as .cpp source file, but unlike regular .cpp, which might be placed into the library first and eventually eliminated by linker, .icpp one is always linked as object file. This forces the file to be always linked. The rationale of this is that you can put module initialization code into .icpp that is linked into the executable even when code is not referenced from other files.


Java files


Python files


Windows resource files.


Layout files. Contain layouts of e.g. dialogs.


Image files. Contain icons and other raster images.


Translation files containing translation of strings used in package to various languages.


Scripts and other meta-information. Contain widget descriptions for layout designer, including visual representation description using ESC scripts.


Project templates.


Fixed macro definitions overrides for Assist++ C++ parser.


TheIDE displays images and if they are smaller than 1024x768, edits them using icon designer.




TheIDE displays images.


U++ rich text format.


Re-definable keys definition file.


Log files.


These files are usually included by some .cpp file(s) for various purposes.


Database schema files. Contain definitions of database layouts. U++ database applications build database schema building scripts from these files and also use them to define structures and constants and variables needed for database interaction.


Skylark HTML templates.


2.2 Special files

There are also files with special meaning. In order to work correctly with U++ and TheIDE environment the names must be exactly the same as in the table below:



This file contains description of importing 3rd party source files contained in package.


This file contains license info for package.


Contains license explanation.


List of authors.


2.3 Other files and directories

There are several file types and directories that you can encounter during your journey with U++. Please noticed that some of these files can be treated in specific way by TheIDE and they are can not be directly edited. Sometimes special designer is required to edit them or they are processed secretly.



Package definition file. Its name must be the same as name of package folder. It is normally managed by TheIDE's package organizer.


Directories with this extension represent Topic++ group. Inside this directories are topic files with the same .tpp extension.


This file inside .tpp directories contains is Topic++ generated file for inclusion of topic group into C++.


Pre-parsed tpp files for fast searching.


Used by BLITZ to properly include icpp files before the rest of the code.


Older format for spelling dictionaries, superseded by .udc


2.4 Settings files

These files stores TheIDE configuration. They are mainly located in TheIDE installation directory. In order to create backup you could copy these files and store them in a convenient location. You can reuse them between your U++ installations or share with your friends.



This is a binary file file takes its name from theide.exe or whatever the name of the executable is that runs the ide. It contains configuration settings which are a serialization of the Setup->Environment dialog.


A text file that contains an assembly configuration as specified in the Assembly setup dialog.


A text file that contains the build settings associated with a particular compiler/ linker ("build method").

cfg folder

This folder holds cache files of TheIDE (tdx,cache,pkg_cache) and configuration files (per package settings, opened files, cursor positions etc.).


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