The Solaris 2.5 environment provides two packages to ease the transition and migration to the SunOS 5.x system software for SPARC systems:
The SunOS/BSD Source Compatibility Package
The SunOS Binary Compatibility Package
If you use these packages, remember that they are a temporary transition aid only for
Developers who want to compile SunOS 4.x application source code to run in the Solaris 2.5 environment.
Users who want to run SunOS 4.x-based application binaries that have not yet been ported to run in a SVID-compliant environment such as the Solaris 2.5 environment.
If this software package is installed, it supports some of the SunOS/BSD commands that are not included in, or have changed in, the SunOS 5.x system software. Application source code that is compliant with the SunOS 4.x environment will compile and run under the Solaris 2.5 environment by using the SunOS/BSD Source Compatibility package.
For specific details, see Binary Compatibility Guide and Source Installation and Media Preparation Guide.
OpenWindows and other executable applications that are either dynamically linked or statically linked and written under SunOS 4.1.x [References to the "SunOS 4.1.x" release/environment include the SunOS 4.1 release and all subsequent 4.1 releases: 4.1.1, 4.1.1 RevB, 4.1.2, 4.1.3, and 4.1.3c.] are supported in the Solaris 2.5 environment through the SunOS Binary Compatibility Package and the OpenWindows Binary Compatibility Package.
To use these packages, applications written under SunOS 4.x must not: