Access through Library Gateways

Introduction
Seattle Public Library
King County Library System
Pierce County Library
Tacoma Public Library
North Olympic Library System
Timberland Regional Library

Introduction

Several public library systems in western Washington include SCN on their dialup menus. While connected, you can use your SCN e-mail and other Internet services in addition to the library catalog.

You can transfer files to and from SCN while connected through one of these systems. But with most of them, it isn't as easy as if you were connected directly to SCN. That's because some library systems don't transmit certain control characters, because their terminal servers would interpret them as unwanted commands.

This is fine for transferring plain text and HTML files. But a system that blocks one or more byte values can prevent the accurate transfer of many kinds of data files. Word processor files, spreadsheet files and graphics files can contain data bytes of any numeric value. When a data value coincides with the numeric value of an unwanted control character, the intermediate system may delete the offending byte from the data stream or translate it to a "harmless" value, thus corrupting the transferred data file.

You can reliably transfer binary data files to SCN through intermediate systems if you first convert all control characters in the files (and all other non-printable characters) into printable ASCII characters, using a standard encoding method that can be reversed by software at the receiving end.

One easy way to transfer binary files to and from SCN is to use the Kermit file transfer protocol in its "text" mode. In text mode, Kermit automatically translates binary files into a form that can pass through any system unchanged. To do this, it uses combinations of printable ASCII characters to represent control characters. Kermit automatically translates the files back into their original form at their destination, making it easy to use.

Many DOS, Windows and Macintosh communications programs include Kermit. If your communications program doesn't support Kermit file transfers, please login to scn.org and look in the program downloads area for some communications programs that do. (Go to the "Work with Your Files" menu and pick "Download Communications and Utility Programs.")

Some programs' versions of Kermit are very slow compared to other file transfer protocols, so using Kermit might not be suitable for lengthy downloads.

Another way to transfer binary files to and from your SCN account is to attach them to e-mail. Pine automatically encodes attached files so that they can be decoded by any mail program that supports the MIME Base 64 encoding that Pine uses. Most current mail programs are compatible with it.

Updated March 25, 2001 - help@scn.org