Linux/IRAF was first released for IRAF V2.10.4 in September 1995. The Linux/IRAF port became one of the most popular IRAF platforms soon after its initial release two years ago and is now second only to SunOS/Solaris in terms of the number of sites in use. As PCs become more popular in astronomy we expect this trend will continue to grow, not only for Linux but other PC Unix systems as well.
The PC-IRAF project involves more than just a Intel Linux port however. Beginning with the IRAF V2.11 release PC-IRAF has become a multi-architecture system supporting not only the original Slackware Linux platform, but also RedHat Linux, FreeBSD and Solaris x86. A single PC-IRAF installation can support any of these platforms if the proper binaries are installed. The new Linux/IRAF versions generate ELF binaries by default, so there should be no problem linking programs (IRAF external packages and IMFORT programs) on Linux systems of recent vintage. Supporting Linux is problematic as there are a number of different distributions and, although they all share the same Linux kernel, they differ enough to be essentially different platforms. We have done the V2.11 upgrade and testing on the most current Redhat and Slackware systems since these seem to be the most popular with our users. F2C/GCC is used to compile all SPP and Fortran code.
FreeBSD is used at NOAO for PC-based network servers and as a development platform for IRAF, and has proven to be a very stable system, as good or better than Linux although not used as extensively in the community. Unlike Linux there is a single FreeBSD distribution. Solaris x86 is unique in that it provides the opportunity to run Solaris software and commercial development tools and compilers on PC platforms. Finally a port to MkLinux (for the Power Macintosh) is planned, which will once again make IRAF available on the Mac. By supporting all these platforms, at least initially, we're better able to compare the merits of each system.
The PC-IRAF distribution will continue to be available freely from the IRAF network archive, but we are also considering a CD-ROM distribution dedicated to PC-IRAF. This experimental CD would contain a live IRAF system allowing you to run any of the architectures and the major IRAF external packages directly from the CD-ROM without installing to local disk. For systems short on disk space such as laptop computers this could be a useful feature. The CD-ROM would also be a convenient way to obtain equivalent versions of all 5 PC-IRAF distributions without excessive download time. The CD-ROM will also contain all the IRAF documentation, including (in some cases) HTML and PostScript versions.
Not much has changed with our suggested hardware requirements for PC-IRAF. Almost any modern PC system is powerful enough to run IRAF with acceptable interactive performance. A 17'' monitor with at least 2 MB video memory is still suggested as is at least 32 MB of RAM; users should consider spending a little extra in these areas to improve performance before upgrading to a faster CPU. 4 MB of VRAM would permit 24-bit truecolor display at high screen resolutions, e.g., 1280 x 1024. The minimum screen resolution recommended for running X11 and IRAF (e.g., on a laptop) is XGA, i.e., 1024 x 768.
Future possible platforms for PC-IRAF include MkLinux as mentioned above (we plan to do the port as soon as the MkLinux DR3 release is available), and looking several years into the future, probably Windows NT. There are no immediate plans to port IRAF to Linux on the Alpha, Alpha PC, or sparc systems, although as always this depends upon how much interest there is in the community.
Doug Tody, Mike Fitzpatrick