DOS ain't dead

when DOS is not DOS (Miscellaneous)

posted by glennmcc  , North Jackson, Ohio (USA), 14.06.2015, 19:42

Was I wrong all these years in thinking that IO.SYS/MSDOS.SYS in earlier
versions of MSDOS and later simply IO.SYS _were_ actually the OS
and that COMMAND.COM was simply the command interpreter ?


> In the beginning, int 0x21 was two MS-DOS system files -
> io.sys and msdos.sys. Originally io.sys was an OEM
> customizable BIOS similar to the earlier CPM's BDOS. When IBM
> introduced the "PC" io.sys was and is an interface to the classic PC
> BIOS. msdos.sys is the low level file system interface. In the
> latest actual DOS version (the one that came with Windows98) io.sys
> contains the functionality of msdos.sys (msdos.sys is actually a
> text file for configuration). io.sys is a high level BIOS and
> while it is the essence of DOS - it's not actually DOS, nor
> is it an operating system - that's the providence of command.com.
>

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Complete thread:

• when DOS is not DOS - mikegonta, 14.06.2015, 15:02 (Miscellaneous)
  • when DOS is not DOS - glennmcc, 14.06.2015, 19:42
    • when DOS is not DOS - mikegonta, 14.06.2015, 19:56
  • when DOS is not DOS - 0ffer, 16.06.2015, 16:50
  • when DOS is not DOS - mikegonta, 17.06.2015, 13:41