Below is my collection of highly-useful *ix scripts. All are hereby placed in the public domain or GPL'd: enjoy, learn and share.

• collapse — Collapse a directory into a gzipped tar file. Requires: bash or ksh, GNU tar, gzip.

• collapse-zip — Same as the above, except that it creates zip files. Requires: bash or ksh, Info-Zip.

• do-backup — A simple wrapper around GNU tar to do a basic system backup. This makes tar work a little more like a PC-type backup program instead of a general data-archiving tool. Requires: recent GNU tar with bzip2 support. (You could hack the script to remove that requirement if you wanted.)

• firewall-enable and firewall-disable — The "enable" script sets up a fairly tight set of firewall rules for a Linux 2.2 system, including masquerading support. Its most important feature is that it's very well-commented, so it's easy to change it to do what you want. The "disable" script turns off these rules, for debugging purposes. Requires: Linux 2.2, ipchains.

• detab — A wrapper around expand(1) that replaces the tabs in any set of files in-place with a series of four spaces. (The number of spaces is, of course, easy to change.) Useful for preparing a collection of text files for use by others who may not use your particular tab preferences. It was used on all these scripts, for example.

• dos2unix — Convert a set of text files in-place to have Unix-style line endings. Yes, I know that there are a billion other versions of this script floating around out there, but this one is here for my convenience: so I can quickly find one that I know works the way I like.

• unix2dos.c — This is similar to the previous script except it performs the reverse conversion. It's a C program only because I couldn't think of a convenient way to write it as a shell script.

• is-dos — A small script that takes a number of files on the command line and detects if they are DOS text files. Requires: hexdump, below.

• hexdump — A wrapper for od(1) that does hex dumping instead of octal. Works with GNU od, at least, and may depend on its unique features.

• randomize — This is a set of tools that run a command on a given set of files, after shuffling the file list. I use these tools for building random slide shows and playing music files back in random order. The scripts deal correctly with difficult issues like quoting filenames with spaces in them. There is no documentation in the package, but there are four sample wrapper scripts that show the ways that these tools can be used. Requires: Perl5.

• showwait, showlist, and showest — The first script shows "wait" states on your network connections. I find this useful mainly for debugging network problems, particularly in programs I've written. The second two scripts show listening sockets and established TCP connections.

• smash-case — Smashes all-uppercase filenames to lowercase; this is useful for files received from MS-DOS machines, and from some CD-ROMs. It can also be asked to smash mixed-case names to all-lowercase. This distinction is helpful because you can say "smash-case *" in a directory and be sure it won't touch files in mixed case, but it will smash the all-uppercase ones.

• faqanntools — This is a collection of tools for creating FAQ announcements via Usenet and via mailing lists. It is fairly rough, and may well not work the way you like. The plus side is that they're open source and easy to change, so you can make them work the way you like! Requires: a C++ compiler and Perl5. They may only build on Linux, but it should be easy to make them work on any Unix flavor with sockets.

• ppp — This is an archive of my Linux PPP configuration files and scripts. It's just here for my convenience.