UNIX SIG By Christopher J. Fearnley Some notes: Next month: "Configuration files" (e.g., .exrc, Xconfig, .fvwmrc, .inputrc, .emacs, /etc/rc.d/rc.local, &etc.,) I've been working a lot with mathematical packages under Linux this month. Hopefully for next month I will be able to review the several packages that I've tried (GNU-Calc, PARI-gp, Octave, and gnuplot). For discussing Linux or UNIX in general, the PACS multi-SIG BBS's UNIX board under magpie is probably the quickest way to contact me. Also, my e-mail is cfearnl@pacs.pha.pa.us, cfearnl@cpp.pha.pa.us or fearnlcj@duvm.ocs.drexel.edu. As many of you know Linux is the most exciting thing happening in the UNIX world today. Version 1.0 was released on March 14, 1994. It is so stable, full-featured and user-friendly that the promise of "Unix for the masses" is becomming a reality. I predict that because of its superior features Linux will be more common in corporate America than DOS within 5 years. There are already some 5 (known) active SIG members who have Linux installed on their systems. Our biggest complaint is that it's so much fun, it starts taking up more and more time! Several more SIG members will install it this month. I recommend getting a distribution based on kernel version 1.0-1.0.9 (higher version numbers are very ALPHA, use at your own risk) which is included in the Slackware 1.2.0 distribution (here higher version numbers are better). Slackware has a very easy to use installation and is the most complete distribution to date. 6. Below are Linux's features as quoted from "the Linux Information Sheet" (one of the HOW-TO documents posted to the internet periodically by Michael K. Johnson - as part of the LDP Linux Documentation Project): Linux Features * multitasking: several programs running at once. * multiuser: several users on the same machine at once (and NO two-user licenses!). * runs in 386 protected mode. * has memory protection between processes, so that one program can't bring the whole system down. * demand loads executables: Linux only reads from disk those parts of a program that are actually used. * shared copy-on-write pages among executables. This means that multiple process can use the same memory to run in. When one tries to write to that memory, that page (4KB piece of memory) is copied somewhere else. Copy-on-write has two benefits: increasing speed and decreasing memory use. * virtual memory using paging (not swapping whole processes) to disk: to a separate partition or a file in the filesystem, or both, with the possibility of adding more swapping areas during runtime (yes, they're still called swapping areas). A total of 16 of these 128 MB swapping areas can be used at once, for a theoretical total 2 GB of useable swap space. * a unified memory pool for user programs and disk cache (so that all free memory can be used for caching, and the cache can be reduced when running large programs). * dynamically linked shared libraries (DLL's)(static libraries too, of course). * does core dumps for post-mortem analysis, allowing the use of a debugger on a program not only while it is running but also after it has crashed. * mostly compatible with POSIX, System V, and BSD at the source level. * through iBCS2-compliant emulation, mostly compatible with SCO, SVR3, and SVR4 at the binary level. * all source code is available, including the whole kernel and all drivers, the development tools and all user programs; also, all of it is freely distributable. There are some commercial programs being provided for Linux now without source, but everything that has been free is still free. * POSIX job control. * pseudoterminals (pty's). * 387-emulation in the kernel so that programs don't need to do their own math emulation. Every computer running Linux appears to have a math coprocessor. Of course, if your computer already contains an FPU, it will be used instead of the emulation, and you can even compile your own kernel with math emulation removed, for a small memory gain. * support for many national or customized keyboards, and it is fairly easy to add new ones. * multiple virtual consoles: several independent login sessions through the console, you switch by pressing a hot-key combination (not dependent on video hardware). * Supports several common filesystems, including minix-1, Xenix, and all the system V filesystems, and has an advanced filesystem of its own, which offers filesystems of up to 4 TB, and names up to 255 characters long. * transparent access to MS-DOS partitions (or OS/2 FAT partitions) via a special filesystem: you don't need any special commands to use the MS-DOS partition, it looks just like a normal Unix filesystem (except for funny restrictions on filenames, permissions, and so on). MS-DOS 6 compressed partitions do not work at this time, and are not expected to. * special filesystem called UMSDOS which allows Linux to be installed on a DOS filesystem. * read-only HPFS-2 support for OS/2 2.1 * CD-ROM filesystem which reads all standard formats of CD-ROMs. * TCP/IP networking, including ftp, telnet, NFS, etc. Legalese Trademarks are owned by their owners. There is no warranty about the information in this document. Use and distribute at your own risk. The content of this document is in the public domain, but please be polite and attribute any quotes.