Packages and Standard DLLs

Create a package when you want to make a custom component that's available through the IDE. Create a standard DLL when you want to build a library that can be called from any application, regardless of the development tool used to build the application.

The following table lists the file types associated with packages:

Package files

File extension	Contents
.bpf	A source file required for a package.
bpi	A Borland package import library. A .bpi is created for each package. The bpis for bpls is analogous to import libraries for dlls. This file is passed to the linker by applications using the package to resolve references to functions in the package. The base name for the bpi is the base name for the package source file.
bpk and bpkw	The project options source file. This file is the XML portion of the package project. The ProjectName.bpk and ProjectName.cpp combined are used to manage settings, options, and files used by the package project. .bpk and .bpkw packages are identical, but use the .bpkw extension for packages that you want to use in cross-platform applications.
bpl	The runtime package. This file is a Windows .dll with special -specific features. The base name for the .bpl is the base name of the .bpk or .bpkw source file.
cpp	ProjectName.cpp contains the entry point for the package. Additionally, each component contained within the package generally resides within a .cpp file.
h	The header file or interface for the component. C omponentN ame.h is the companion to C omponentN ame.cpp.
lib	A static library, or collection of .objs , used in place of a .bpi when the application does not use runtime packages. Generated only if the -Gl (Generate .lib file) linker option is selected.
obj	A binary image for a unit file contained in a package. One .obj is created, when necessary, for each .cpp file.

Note: Packages share their global data with other modules in an application.