History of DOS, Part 4 - China DOS Union Forum - China DOS Union

Sender: ccccccc (Big Mouth★BBS Syndrome), Board: DOS
Title: History of DOS, Part 4
Posted at: Shuimu Tsinghua BBS (Thu May 20 01:12:42 1999)

Sender: dos (Little White Rabbit), Board: DOS
Title: History of DOS, Part 4
Posted at: Yixian Shikong Yat-sen Channel (Sun Apr 4 10:30:01 1999), on-site mail

The earliest IBM PCs were floppy-disk-based systems, using floppy drives A and B. The earliest PCs did not support the very expensive hard disks of that time. When IBM announced the IBM PC XT plan including a 10MB hard disk, Microsoft developed a new file system for DOS. MS-DOS version 1.0 and version 1.1 did not support hierarchical directories, but for hard disks, such directories were necessary.
Microsoft chose to develop a hierarchical directory structure similar to that of minicomputer UNIX operating systems. UNIX was beginning to become popular at the time. Since file control blocks did not support the space needed for directory path names, Microsoft retained the file control block and made version 2.0 manage files based on file handles. A second advantage of DOS using file handles was that it could implement redirection (also a common feature of UNIX).
With DOS version 2.0, IBM became very successful, and DOS together with the CP/M operating system became optional operating systems. Because of the popularity of the PC, many hardware manufacturers developed PC-based products. To help these manufacturers integrate their products, MS-DOS 2.0 provided support for installable device drivers, and for the first time provided the CONFIG.SYS preconfiguration file. DOS version 2.0 included many UNIX features; however, UNIX is a multi-user operating system that allows many users to run multiple programs simultaneously.
To provide a simplified form of multitasking, DOS version 2.0 provided memory-resident programs such as GRAPHICS and PRINT.
After DOS version 2, Microsoft also released MS-DOS 2.01, which supported international character sets. During this period, IBM introduced its short-lived IBM PCJr computer. To support the PCJr, Microsoft also developed PC-DOS 2.1 for IBM. Later Microsoft combined these two latest DOS versions to produce MS-DOS 2.11. In 1983, Microsoft released MS-DOS 2.25, which included troubleshooting and support for the extended ASCII character set.

--
※ Source:·Shuimu Tsinghua BBS bbs.net.tsinghua.edu.cn·

(This article was copied using the S-Term article copy script)
==================================================

Floor1　ko20010214	Posted 2003-06-01 00:00
版主　Posts 1,628　Credits 7,296
Sender: ccccccc (Big Mouth★BBS Syndrome), Board: DOS Title: History of DOS, Part 4 Posted at: Shuimu Tsinghua BBS (Thu May 20 01:12:42 1999) Sender: dos (Little White Rabbit), Board: DOS Title: History of DOS, Part 4 Posted at: Yixian Shikong Yat-sen Channel (Sun Apr 4 10:30:01 1999), on-site mail The earliest IBM PCs were floppy-disk-based systems, using floppy drives A and B. The earliest PCs did not support the very expensive hard disks of that time. When IBM announced the IBM PC XT plan including a 10MB hard disk, Microsoft developed a new file system for DOS. MS-DOS version 1.0 and version 1.1 did not support hierarchical directories, but for hard disks, such directories were necessary. Microsoft chose to develop a hierarchical directory structure similar to that of minicomputer UNIX operating systems. UNIX was beginning to become popular at the time. Since file control blocks did not support the space needed for directory path names, Microsoft retained the file control block and made version 2.0 manage files based on file handles. A second advantage of DOS using file handles was that it could implement redirection (also a common feature of UNIX). With DOS version 2.0, IBM became very successful, and DOS together with the CP/M operating system became optional operating systems. Because of the popularity of the PC, many hardware manufacturers developed PC-based products. To help these manufacturers integrate their products, MS-DOS 2.0 provided support for installable device drivers, and for the first time provided the CONFIG.SYS preconfiguration file. DOS version 2.0 included many UNIX features; however, UNIX is a multi-user operating system that allows many users to run multiple programs simultaneously. To provide a simplified form of multitasking, DOS version 2.0 provided memory-resident programs such as GRAPHICS and PRINT. After DOS version 2, Microsoft also released MS-DOS 2.01, which supported international character sets. During this period, IBM introduced its short-lived IBM PCJr computer. To support the PCJr, Microsoft also developed PC-DOS 2.1 for IBM. Later Microsoft combined these two latest DOS versions to produce MS-DOS 2.11. In 1983, Microsoft released MS-DOS 2.25, which included troubleshooting and support for the extended ASCII character set. -- ※ Source:·Shuimu Tsinghua BBS bbs.net.tsinghua.edu.cn· (This article was copied using the S-Term article copy script) ==================================================