PackIt
 | |
| Developer(s) | Harry Chesley (unsupported) |
|---|---|
| Stable release | PackIt III v1.3
/ 1986 |
| Operating system | Classic Mac OS |
| Type | File Compressor |
| License | Shareware |
| Website | Packit |
PackIt is a
Apple Macintosh platform. It was the first such program to see widespread use on the Mac, and most Mac software archives accepted uploads only in PackIt format for some time. StuffIt
, introduced in the summer of 1987, offered much improved compression, and PackIt quickly disappeared.
PackIt was written by Harry Chesley to support an online magazine he was writing for at the time, MacDeveloper. To distribute code and sample applications, he needed to archive a number of files into one for transmission. In the original version this was done in a simple manner, simply placing the Finder file information, data fork and
tar
utility in concept. Like tar, the format did not include an archive header of any sort. To extract the nth file, PackIt had to read past all of the n-1 files first.
PackIt II was released in early 1986 and added
Apple Computer
, and work on PackIt ended.
In comparison, StuffIt supported the newer
LZW
-type compression system and compressed the data and resource forks separately. This led to significantly better compression ratios on almost all files. The files were then stored with a single universal header, allowing the program to quickly list the archive contents, as well as uncompress a single file, without having to "scan" through the archive. This made StuffIt much easier and faster to use in practice.
Archives created with PackIt used the .pit
file extension. File extensions are not normally needed on the Mac, but were commonly used on archives because they would typically be stored on some other system that would require them (PC's for instance). These files were generally stored in MacBinary
format on such machines, however, making the extension somewhat superfluous. Later versions of PackIt would recognize a MacBinary header if it had been left on, and strip it off automatically.
References
- E-mail with the author
External links
- PackIt - Harry Chesley's "home page" for PackIt, including source code
- UnPackIt source code
- Archive Formats and Data - contains a section on the PackIt header format
- macutils, converts between different Macintosh file encodings; supposedly can unpack PackIt archives