You may have followed the threads about the priority of PM drawing
  operations, and you may have seen my message describing the poking of
  the OS/2 kernel. I had no hex editors on my disk because of my hard
  disk crash, and not a single C or Pascal compiler to make a program to
  modify the kernel, so I wrote one in REXX.

  It turns out that in addition to its text processing capabilities,
  REXX is quite capable of handling binary data as well.

  So, if you feel like poking the kernel priority table, here is this
  REXX script to ease your job.

  It is written in OREXX, so if you use plain REXX - sorry... I'm
  learning OREXX right now, so I wrote it in OREXX. But it can very
  easily be changed to plain REXX, if you don't feel like changing your
  interpretter.

  Don't forget to change the first two variables to suit your system!
  Also, remove the ReadOnly, System and Hidden attributes from your
  OS2KRNL file.

  Here goes:

=================================================================
/* Editor za tabelata na prioriteti vo OS/2 kernelot */

KernelName = "C:\OS2KRNL"
Editor = "fte"  /* For editing the textual representation of the table */


TableSig = "0300 0100 0200 0800 0300 0100 0200 0800"

Tail.0  = 16
Tail.1  = "----"
Tail.2  = "---S"
Tail.3  = "--D-"
Tail.4  = "--DS"
Tail.5  = "-F--"
Tail.6  = "-F-S"
Tail.7  = "-FD-"
Tail.8  = "-FDS"
Tail.9  = "W---"
Tail.10 = "W--S"
Tail.11 = "W-D-"
Tail.12 = "W-DS"
Tail.13 = "WF--"
Tail.14 = "WF-S"
Tail.15 = "WFD-"
Tail.16 = "WFDS"


say
say "                         !!!!! WARNING !!!!!"
say
say "This program is about to modify your OS/2 kernel file
("KernelName")!"
say "Make sure you have a backup copy of it, this program DOESN'T make a 
backup!"
say "Press Ctrl-C to exit now, or ENTER to continue..."
call Beep 1000, 250
.Input

Kernel = .Stream~New(KernelName)
if Kernel~Query("Exists") == "" then do
  say "Fajlot" KernelName "ne postoi"
  return
end
if Kernel~Open("Binary")  "READY:" then do
  say "Ne mozam da go otvoram fajlot" KernelName
  return
end

KernelData = Kernel~CharIn( , Kernel~Query("Size"))
TableOfs = KernelData~Pos(ConvertEndian(TableSig~X2C))
if TableOfs == 0 then do
  say "Cannot find priority table in kernel file."
  say "Did you unpack the kernel with LXLite?"
  exit 1
end

TempName = "PriTab.tmp"
call ToText TempName, TableOfs
Editor TempName
call FromText TempName, TableOfs

Kernel~Seek(1 "Write")
Kernel~CharOut(KernelData)
Kernel~Close()
return 0

ConvertEndian: procedure
  parse arg s
  s = s~Space(0)
  if s~Length // 2  0 then do
    say "Invalid HexString"
    exit 1
  end
  do i = 1 to s~Length by 2
    s = s~Overlay(s~SubStr(i, 2)~Reverse, i)
  end
return s

ToText: procedure expose KernelData Tail.
  parse arg TempName, TableOfs
  Temp = .Stream~New(TempName)
  if Temp~Open("Write Replace")  "READY:" then do
    say "Ne mozam da go otvoram fajlot" TempName
    exit 1
  end
  do n = 1 to 16
    Linija = ConvertEndian(KernelData~SubStr(TableOfs, 16))~C2X
    pom = ""
    do i = 1 to Linija~Length by 4
      pom = pom||Linija~SubStr(i, 4)||"    "
    end
    Temp~LineOut(pom||Tail.n)
    TableOfs = TableOfs + 16
  end
 
Temp~LineOut("----------------------------------------------------------")
  Temp~LineOut("Server  Idle    Regular TC    | Server  Idle   
Regular TC")
  Temp~LineOut("Not Keyboard (04)             | Keyboard (04)")
  Temp~LineOut("")
  Temp~LineOut("Starved         08")
  Temp~LineOut("Device I/O      10")
  Temp~LineOut("Foreground      20")
  Temp~LineOut("Window          40")
  Temp~LineOut("VDM Interrupt   80")
  Temp~Lineout("")
  Temp~LineOut("Note: Use OVERTYPE mode for best editing")
  Temp~Close
return 0

FromText: procedure expose KernelData
  parse arg TempName, TableOfs
  Temp = .Stream~New(TempName)
  if Temp~Open("Read")  "READY:" then do
    say "Ne mozam da go otvoram fajlot" TempName
    exit 1
  end
  do 16
Linija = Temp
    Linija = ConvertEndian(Linija~Space(0)~SubStr(1,32)~X2C)
    KernelData = KernelData~Overlay(Linija, TableOfs)
    TableOfs = TableOfs + 16
  end
  Temp~Close
return 0
==================================================================

                                                            - Ivan -

.!. Word is a shadow of deed.             Democritus (400 BC)
--- Terminate 5.00/Pro [OS/2]
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