Portable Object Compiler

The Portable Object Compiler, a language and a runtime library for producing C programs that operate by the runtime conventions of Smalltalk 80 in a UNIX environment, as described in Brad Cox's book on Objective-C or in his Producer paper.

Objective-C and Smalltalk 80 offer Object Oriented Programming in which data, and the programs which may access it, are designed, built and maintained as inseparable units called objects.

The Portable Object Compiler is backed by a library which supports Smalltalk 80's interpretation of messaging; binding of a message to its target routine is done at run time. This library contains a growing number of primitive class definitions, such as an Object class whose abilities are inherited by every object in the system, and provides many, but not all, capabilities of Smalltalk. The language provides features such as Blocks, also known as enclosures.

The software has been ported to many flavors of UNIX and non-UNIX operating systems, with, as the name suggests, a special emphasis on portability. Ports exist for Solaris SPARC, IBM AIX PowerPC, DEC Alpha, HP-UX PA-RISC and HP-UX IA-64, Silicon Graphics IRIX MIPS, Linux, BSD and many other ports.

The compiler is compatible with, and can be used with many different C compilers, such as clang, gcc, Intel icc, Sun DeveloperStudio cc, lcc, tcc and great variety of other C compilers in order to generate optimal code for each specific platform and purpose.

Because the compiler is written in itself, you'd normally start with a binary package of the software. For a few platforms, there are also packages of the shared libraries of the software, useful for applications that depend on those shared libraries :

Solaris 11.3 P5P (see 'man pkgrecv') archive objc-3.3.14-sol11.3-i386.p5p.gz and objclibs-3.3.14-sol11.3-i386.p5p.gz (32bit for DeveloperStudio 12.6).
Solaris 11.4 P5P (see 'man pkgrecv') archive objc-3.3.14-sol11.4-x64.p5p.gz and objclibs-3.3.14-sol11.4-x64.p5p.gz (64bit for DeveloperStudio 12.6).
Slackware 14.2 tgz objc-3.3.11-x86_64-1_stes.tgz (Slackware 14.2 for gcc 5.3 or clang 3.8).
SuSE Linux SLES 15 rpm objc-3.3.13-1.x86_64.rpm (for gcc 7).
RedHat Linux RHEL 6.0 rpm objc-3.3.11-1.el6.i386.rpm and objclibs-3.3.11-1.el6.i386.rpm (for gcc 4.4.4 32bit).
RedHat Linux RHEL 7.0 rpm objc-3.3.11-1.el7.x86_64.rpm and objclibs-3.3.11-1.el7.x86_64.rpm (for gcc 4.8.3 64bit).
Fedora Linux 29 rpm objc-3.3.14-1.fc29.x86_64.rpm and objclibs-3.3.14-1.fc29.x86_64.rpm (for gcc 8.3.1 64bit).
Ubuntu 18.4.2 deb objc_3.3.13_amd64.deb (Debian package for gcc 7.3).
FreeBSD 10.4 x86:32 pkg objc-3.3.12.txz (for clang 3.4.1, installs in /usr/local)
FreeBSD 11.2 x86:64 pkg objc-3.3.13.txz (for clang 6.0.0, installs in /usr/local)
Dragonfly BSD 5.4 x86:64 pkg objc-3.3.12.txz (for gcc 8.1 x86_64 installs in /usr/local)
Microsoft Windows oc319v.zip (for Microsoft Visual C++ 6.0)
Microsoft Windows oc319w.zip (for Watcom)

On Linux or UNIX systems, you should install the sources of the software as follows :

Compile or install flex
Install (for example by "yum install byacc") or compile BSD byacc ("bison -y -d" could be used as alternative but preferably use 'byacc')
Install a binary version of the Portable Object Compiler from one of the above links. The compiler is written in itself, so you need a bootstrap compiler (one of those binary packages) to start.
Install objc-3.3.14.tar.gz.
Optionally, for the class browser, install cursel-0.2.4.tar.gz.

Optionally for expert users porting to new or other platforms, where there is no binary package available, build objc-bootstrap-3.3.13.tar.gz.

The package contains the documentation in HTML format. The manual is also available here, and there's a note on Objective-C blocks. The text Objective-C for Unix is also a source of information on the architecture of the compiler.

Metalab : http://metalab.unc.edu/pub/Linux/devel/lang/objc/.

More Objective-C packages can be found at Metalab : http://metalab.unc.edu/pub/Linux/devel/lang/objc/.

CheezMUD, a MUD written in Objective-C, is not in the /devel/lang/objc directory, but rather in http://metalab.unc.edu/pub/Linux/games/muds/.

Richtext is an X11 / Motif / Lesstif text editor (and RTF file previewer) written in Objective-C and available at http://metalab.unc.edu/pub/Linux/apps/editors/X/.

Here's a screenshot of the Richtext previewer/editor on Slackware (or FreeBSD) with a KDE desktop and another screenshot on Solaris 11.3 (with a GNOME 2 desktop). Another screenshot on Solaris 11.4 with the GNOME 3 desktop.