building-software

This document, "Building Open Source Software on DEC ULTRIX V4.5" by Joachim Buss (dated September 1, 2002), serves as a guide for compiling open-source software on the DEC ULTRIX V4.5 operating system for RISC and VAX architectures. It highlights that ULTRIX is an old, obsolete BSD-style UNIX, yet remains the only official proprietary OS for DEC RISC and is the fastest for both VAX and RISC with full hardware support, making software compilation a "tricky" process.

Key advice includes:

1. System Software: Install the full ULTRIX distribution, including "UNSUPPORTED" subsets. Address Y2K issues using a patch kit or a specific date-setting workaround (as ULTRIX does not support years after 2038). Replace the obsolete /bin/sh with /usr/bin/ksh.
2. Compiling Applications:
   • Check NetBSD package pages for dependencies due to incomplete documentation.
   • Generally, prefer gcc (specifically gcc-2.95.2 for RISC, gcc-2.8.1 for VAX) over DEC's native cc2.1, cc3.0, or vcc, though older programs might compile with cc3.0.
   • Allocate ample swap space (e.g., 128MB RAM + 256MB swap for RISC with gcc) to prevent "virtual memory exhausted" errors.
   • Link with -liberty if the strdup symbol is missing, and edit sources to use alternative functions like napms if usleep is unavailable.
   • For gcc-2.7.2 and gcc-2.8.1, softlink gcc to c++ as the bundled GNU C++ is problematic.
3. X Window System: MIT X11R6.1 builds well with DEC C and is recommended for the newest working X-server (Xdec). Upgrade to X11R6.1 before compiling newer X applications, cleaning up older X11 environments first.
4. GNU Replacements: Replace obsolete ULTRIX components like ld, cxx, and make with newer GNU equivalents (e.g., binutils-2.10, gcc-2.95.2, make-3.79). Crucially, the native ULTRIX ld must be used for kernel compilation. Other Y2K-incompatible ULTRIX components can also be replaced with GNU/Open Source versions if the Y2K patch kit is unavailable.

The document also provides contact information, links to ULTRIX freeware archives, and a disclaimer that the advice is offered without guarantee and should be used at the user's own risk, ideally with system backups. Contributions of compiled software or cross-compiler environments are welcomed.