SDF

Simple Document Format, a system for writing documentation. It's vaguely like Perl's POD system (and can be seen as a set of extensions to it). The text markup is designed to be author friendly (unlike, say, HTML which is plain weird, or XML which is still quite verbose). Backends exist to translate SDF to a variety of different formats.

Learn more at www.freeshell.org


SDF is also an acronym for a "free", publicly funded UNIX server. According to the website, the system has been in operation since 1988 (presumably on dialup).

Application is simple. Log onto sdf.lonestar.org using "plain" telnet, and make a temporary account. This interim account is limited to pine, ls, dir, and cd, so it isn't the idea base for any sort of malicious behavior.

If so inclined, you can send in one dollar, one euro, or equivalent to some shady P.O. Box. Of course, practice common sense when sending green stamps through the USPS. This uprated account gives you a pretty wide selection of commands including mkdir and rm, as well as elm, tin but alas no telnet. The website for SDF gives more info on how to trade money for more commands, and even a good share of server space. Again, this is at the user's discretion.

In my few months of using SDF, service has been good. The only delays in service have been for server or equipment upgrades. The owners make themselves available, and things seem pretty legit if, again, one practices a bit of healthy identity protection. There are some nice advantages to having a real server to plop mailing lists on, most of all a bit of freedom from endless reams of spam that can plague Web based "free" email services.

In French, common abbreviation for "sans domicile fixe", i.e. of no fixed abode, homeless, generally used as a a noun (un essdéyeff) to mean a homeless person; features in the names of various Big Issue-style self-help publications (or exploitative imitations of them).

Electronics Terminology: SDF

In microelectronics, SDF stands for Standard Delay Format.

An SDF file is specific to a particular electronic circuit design and contains estimated timing delay information for all the logic gates, ("gate delay"), and associated interconnect, ("net delay"), in that design. SDF files are generated by analysis of the design netlist. There are two broad types of SDF:

• Pre-Layout SDF: Generated before design goes to layout. Gate delays derived from vendor library. Net delay estimated by drive strength of driving cell, capacitive load of inputs being driven and fanout.
• Post-Layout SDF: After layout of the design is complete, physical information relating to interconnect can be used to provide more accurate delay estimation.

This information, in conjunction with the design netlist itself, can be used to evaluate the timing performance of a design prior to manufacture. Such analysis can be conducted by "dynamic", (i.e. simulation), or "static", ("STA"), means.

Social Development Fund. UK gov