Stuffit deluxe 201012/27/2023 Called PowerTalk, it never really caught on, and was abandoned with Mac OS 7.6. One of the good ideas in PowerTalk was the personal keychain, an encrypted database to store all those pesky user ID's and passwords collected while cruising the 'Net. PowerTalk is long gone, but the personal keychain is back. The most spectacular part of the whole multiple-user setup is voiceprint passwords. When this is turned on, a user can log into the system by speaking a phrase into the microphone. The Mac analyzes her voice patterns to decide whether it's really her. My experience with voice recognition is somewhat mixed. On a desktop machine it was quite reliable, but on a PowerBook it was not. The problem with the PowerBook was probably because the acoustics changed as the machine moved around. Apple had one of their traveling 'demo the new wares' shows in Louisville recently, and their own pitchman couldn't get it to work. He'd recorded the pass-phrase at home and it refused to work in front of the crowd. Luckily, the user ID and password can still be typed in.Īpple is in the process of abandoning classical AppleTalk in favor of worldwide networking standards. The most useful major addition to Mac OS 9 is its wholesale embrace of TCP/IP. AppleScript can now send Apple Events via TCP/IP and, most importantly, desktop workstations can now use TCP/IP personal file sharing.File sharing over TPC/IP has been around for several years on the Mac, but it was limited to expensive AppleShare/IP file servers or the open source Netatalk-based servers under Unix and Linux. With the new file sharing, anyone running Mac OS 9 will be able to share volumes worldwide over the Internet. Weaving it's way throughout Mac OS 9 is Apple's first big move toward 'Carbon.' This arises from Apple's plans to have two full-blown operating systems by the end of next year. One of them will be some version of Mac OS 9, and the other will be a newer version of Mac OS X able to run Macintosh programs. 'Carbon' is the glue allowing the same programs to run on each. More precisely, Carbon, is the new set of rules and routines programmers must follow to ensure their programs will work with both operating systems. Apple published the Carbon specifications about 18 months ago, and advised all programmers to follow the new guidelines. Mac OS 9 is the first OS to contain CarbonLib, a library of shared routines available to Carbon-based programs. In fact, key programs such as the new Finder 9.0, AppleScript 1.4 and Script Editor 1.4 are already Carbon-based. Mac OS 9 still contains the older shared libraries so non-Carbon-based programs will still work. So after all of this and many more new goodies, should Mac OS 9 be your operating system? Ummm. Huffman tables, Unary base 1 encoding, Delta encoding, and Sparse bit array are also used.There are many programs that have serious problems with Mac OS 9. Huffman coding replaces fixed length symbols based on frequency of use, shortening sequences used regularly throughout the code. Run length encoding replaces long strings of repeated symbols by combining a symbol and sequence of two special codes (RUNA, RUNB), decreasing repeated symbols with codes and the number of repeated symbols. Symbols are processed and replaced by location and moved to the front. Move to front transformation does not alter the size of processed blocks. Blocks are self-contained with an operating limit of 900 kB. Burrows-Wheeler transformation is a reversible block-sort transformation. Run-length encoding replaces sequences of 4-255 consecutive duplicate symbols. Decompression of these files is generally quick.ĭifferent layers of compression are used and stacked in the process of creating BZ2 files. Conversion is accomplished by taking data in blocks (100-900 kB in size) and using the Burrows-Wheeler transformation to convert characters which occur regularly into strings of identical letters, then applying “move-to-front” transformation and Huffman coding. This form of data compression is more efficient and effective than older methods (Z, ZIP, GZ, etc) but it is a slower process. This program uses the Burrows-Wheeler algorithm to compress single files, as opposed to a file archiver. BZ2 files refer to the free and open source file compression bzip2 program files.
0 Comments
Leave a Reply.AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |