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IBM PC DOS 4.00

PC DOS 4.00 was released in July 1988.

A Feature Summary, along with Directory Listings of the five 360Kb distribution diskettes, are provided below.

[PCjs Machine "ibm5170-pcdos400"]

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Feature Summary

New features:

Another significant change in DOS 4.00 was the ability to update the system files (IBMBIO.COM and IBMDOS.COM in PC DOS, or IO.SYS and MSDOS.SYS in MS-DOS) of any boot disk, by moving the first two directory entries (and the contents of the first three data sectors) as needed to make room for the new system files.

The SYS command in older versions of DOS would report “No room for system on destination disk” if the first two directory entries (or the first three data sectors) were unavailable. However, after using the DOS 4.00 SYS command, it usually became possible to install older DOS versions as well.

Learn more about the history of the SYS command from Microsoft Support.

New internal commands:

New external commands:

New CONFIG.SYS commands:

New device drivers:

New support files:

New functions:

Directory of PC DOS 4.00 (Disk 1)

 Volume in drive A has no label
 Directory of A:\

IBMBIO   COM*    32816   8-03-88  12:00p
IBMDOS   COM*    36000   8-03-88  12:00p
COMMAND  COM     37637   6-17-88  12:00p
AUTOEXEC BAT        39   6-17-88  12:00p
CONFIG   SYS        96   6-17-88  12:00p
COUNTRY  SYS     12838   6-17-88  12:00p
DISKCOPY COM     10428   6-17-88  12:00p
DISPLAY  SYS     15741   6-17-88  12:00p
FDISK    COM     70151   6-17-88  12:00p
FORMAT   COM     22923   6-17-88  12:00p
KEYB     COM     14759   6-17-88  12:00p
KEYBOARD SYS     23360   8-03-88  12:00p
REPLACE  EXE     17199   6-17-88  12:00p
SELECT   COM      3674   8-03-88  12:00p
SELECT   HLP     27562   8-03-88  12:00p
SELECT   PRT      1594   8-03-88  12:00p
SYS      COM     11472   6-17-88  12:00p
012345   678       109   6-17-88  12:00p
DOS00I   400*        0   6-17-88  12:00p
       19 file(s)     338398 bytes
                       17408 bytes free

Directory of PC DOS 4.00 (Disk 2)

 Volume in drive A has no label
 Directory of A:\

COMMAND  COM     37637   6-17-88  12:00p
ASSIGN   COM      5785   6-17-88  12:00p
ATTRIB   EXE     18247   6-17-88  12:00p
BASIC    COM      1065   6-17-88  12:00p
BASICA   COM     36285   6-17-88  12:00p
COMP     COM      9491   6-17-88  12:00p
DEBUG    COM     21606   6-17-88  12:00p
DISKCOMP COM      9889   6-17-88  12:00p
EDLIN    COM     14249   6-17-88  12:00p
FILESYS  EXE     11125   6-17-88  12:00p
FIND     EXE      5983   6-17-88  12:00p
IFSFUNC  EXE     21653   8-03-88  12:00p
JOIN     EXE     17457   6-17-88  12:00p
LABEL    COM      4490   6-17-88  12:00p
MEM      EXE     20133   6-17-88  12:00p
MODE     COM     23056   8-03-88  12:00p
MORE     COM      2166   6-17-88  12:00p
MORTGAGE BAS      6207   6-17-88  12:00p
SHARE    EXE     10301   8-03-88  12:00p
SORT     EXE      5914   6-17-88  12:00p
SUBST    EXE     18143   6-17-88  12:00p
TREE     COM      6334   6-17-88  12:00p
XCOPY    EXE     17087   6-17-88  12:00p
DOS01I   400*        0   6-17-88  12:00p
       24 file(s)     324303 bytes
                       30208 bytes free

Directory of PC DOS 4.00 (Disk 3)

 Volume in drive A has no label
 Directory of A:\

COMMAND  COM     37637   6-17-88  12:00p
CHKDSK   COM     17771   6-17-88  12:00p
DISKCOPY COM     10428   6-17-88  12:00p
PCIBMDRV MOS       295   6-17-88  12:00p
PCMSDRV  MOS       961   6-17-88  12:00p
PCMSPDRV MOS       801   6-17-88  12:00p
PRINT    COM     14024   8-03-88  12:00p
SHELL    CLR      4438   6-17-88  12:00p
SHELL    HLP     65667   8-03-88  12:00p
SHELL    MEU      4588   8-03-88  12:00p
SHELLB   COM      3937   8-03-88  12:00p
SHELLC   EXE    154377   8-03-88  12:00p
DOSUTIL  MEU      6660   6-17-88  12:00p
012345   678       109   6-17-88  12:00p
DOS02I   400*        0   6-17-88  12:00p
       15 file(s)     321693 bytes
                       36352 bytes free

Directory of PC DOS 4.00 (Disk 4)

 Volume in drive A has no label
 Directory of A:\

IBMBIO   COM*    32816   8-03-88  12:00p
IBMDOS   COM*    36000   8-03-88  12:00p
COMMAND  COM     37637   6-17-88  12:00p
ANSI     SYS      9148   6-17-88  12:00p
APPEND   EXE     11186   8-03-88  12:00p
COUNTRY  SYS     12838   6-17-88  12:00p
DISPLAY  SYS     15741   6-17-88  12:00p
DRIVER   SYS      5274   6-17-88  12:00p
FASTOPEN EXE     16302   6-17-88  12:00p
GRAFTABL COM     10271   6-17-88  12:00p
GRAPHICS COM     16733   6-17-88  12:00p
GRAPHICS PRO      9413   6-17-88  12:00p
KEYB     COM     14759   6-17-88  12:00p
KEYBOARD SYS     23360   8-03-88  12:00p
MODE     COM     23056   8-03-88  12:00p
NLSFUNC  EXE      6910   6-17-88  12:00p
PRINTER  SYS     18946   6-17-88  12:00p
RECOVER  COM     10732   6-17-88  12:00p
VDISK    SYS      6376   6-17-88  12:00p
4201     CPI      6404   6-17-88  12:00p
4208     CPI       641   6-17-88  12:00p
5202     CPI       402   6-17-88  12:00p
DOS03I   400*        0   6-17-88  12:00p
       23 file(s)     324945 bytes
                       30720 bytes free

Directory of PC DOS 4.00 (Disk 5)

 Volume in drive A has no label
 Directory of A:\

BACKUP   COM     33754   6-17-88  12:00p
EGA      CPI     49052   6-17-88  12:00p
FORMAT   COM     22923   6-17-88  12:00p
LCD      CPI     10592   6-17-88  12:00p
MODE     COM     23056   8-03-88  12:00p
RESTORE  COM     40030   6-17-88  12:00p
SELECT   DAT     22453   8-03-88  12:00p
SELECT   EXE     99545   8-03-88  12:00p
XMAEM    SYS     19312   6-17-88  12:00p
XMA2EMS  SYS     29249   8-03-88  12:00p
DOS04L   400*        0   6-17-88  12:00p
       11 file(s)     349966 bytes
                        9216 bytes free

Directory of PC DOS 4.00 (TechRef)

 Volume in drive A has no label
 Directory of A:\

DEBUG    COM     21606   6-17-88  12:00p
EXE2BIN  EXE      7973   6-17-88  12:00p
LIB      EXE     47107   6-17-88  12:00p
LINK     EXE    105406   6-17-88  12:00p
VDISK    ASM     75571   6-17-88  12:00p
        5 file(s)     257663 bytes
                      102400 bytes free