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QuickFiler/WSWI-Help
This website contains an archive of files for the Acorn Electron, BBC Micro, Acorn Archimedes, Commodore 16 and Commodore 64 computers, which Dominic Ford has rescued from his private collection of floppy disks and cassettes.
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- Archimedes archive » Acorn User » AU 1998-12.adf » Regulars » StarInfo/Fletcher/!Purple/WSWI-Help
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File contents
WimpSWIVe 0.05 (30 Oct 1995)
==================================
NewerLook needs to trap Wimp_ SWIs in order to provide its new error
windows. The only official way to trap SWIs is to trap the SWI hardware
vector, but even this is not recommended. It takes much code to implement
properly in *all* circumstances (about 30K of source code in Desktop Hacker),
and can slow the machine down, quite considerably when there are multiple
claimants.
It is, however, possible to trap Wimp_ SWIs by providing another module
with the same SWI chunk and names. This method is much quicker and easier,
but it is - as I�ll happily admit - rather dodgy. One of the problems is
that only one module can do this at a time. So if NewerLook had a module
that used this method, it wouldn�t work properly when another program tried
to do the same thing. (And you know some program will.)
Thus, I have separated the trapping code from the action code (which resides
in another module), and released this module separately. It can manage SWI
claims and releases dynamically, a bit like vectors. Actually, quite a lot
like vectors. You can use it in your own programs if you like. Here�s how.
Because WimpSWIVe uses the Wimp�s SWI chunk, it cannot provide its own
SWIs. Instead, it communicates using a Wimp SWI, namely Wimp_RegisterFilter.
Here is the WimpSWIVe specification for Wimp_RegisterFilter.
| Wimp_RegisterFilter
| (SWI &400F5)
|
| Used by the Filter Manager to register or deregister a filter
| OR used to register SWI claims and releases with WimpSWIVe
|
On entry: | R0 = reason code:
| &49575357 (�WSWI�) for WimpSWIVe operation (see below)
| anything else for filter operation (see RISC OS 3
| Programmers� Reference Manual, page 3-224)
| R1 = SWI word:
| bits 0-5 : offset in SWI chunk of SWI to claim/release
| bit 6 : ignore bits 0-5 and claim all Wimp_ SWIs
| bits 7-29: undefined, leave unset
| bit 30 : high priority if set, else low priority
| bit 31 : claim if set, else release
| R2 = value to be passed in R12 on entry to code
| R3 = address of SWI pre-trapping code, or 0 if none needed
| R4 = address of SWI post-trapping code, or 0 if none needed
|
On exit: | Registers preserved
|
Interrupts: | Interrupts may be enabled
| Fast interrupts may be enabled
|
Processor: | Processor is in SVC mode
|
Reentrancy: | SWI is not re-entrant
|
Use: | In WimpSWIVe usage, this SWI is used to claim or release SWIs.
| The pre-trapping code specified is called before the SWI is
| called, and the post-trapping code afterwards.
|
| High-priority pre-code is called before low priority pre-code.
| (And high-priority post-code is called after low priority
| post-code.) This is important because one piece of pre-code
| could intercept a SWI call before another bit got a look in.
| You should use high-priority code for monitoring and register-
| altering code. If your pre-code is at all likely to intercept
| a SWI, you must use low-priority code. In effect, low-priority
| code is �closer� to the real SWI.
|
| Pre-trapping code conditions:
|
| On entry: R0-R8 = registers passed to SWI
| R9 = offset into chunk of SWI called
| R12 = value specified when RegisterFilter called
| R13 = full, descending stack
| R14 = return address
| On exit: R0-R8 = may be altered to change effect of SWI
| R9 = preserved, or -1 to intercept SWI
|
| Pre-trapping code is entered in SVC mode, with interrupts
| disabled. If R9=-1 on exit, the SWI is not called. Instead,
| any outstanding post-code is called, and the caller is returned
| to with the supplied R0-R8 and PSR flags. An error may be
| signified by pointing R0 to an error block and setting the V
| flag on return as normal, when intercepting. (See footnote 1.)
|
| If more than one client has claimed a SWI, it is the earliest
| claimant�s pre-trapping code that is called last - new
| claimants take priority (though high-priority always beats low-
| priority, of course). If interception occurs, any post-trapping
| code for claims where the pre-trapping code (if any) has
| already been executed are also executed. In effect, you are
| guaranteed that you will get a post-trap event if you have had
| a pre-trap. (See footnote 2.)
|
|
| Post-trapping code conditions:
|
| On entry: R0-R8 = registers passed back from SWI
| R9 = offset into chunk of SWI called
| R12 = value specified when RegisterFilter called
| R13 = full, descending stack
| R14 = return address
| On exit: R0-R8 = may be altered to change perceived results
| PSR flags may be altered to change perceived results
| (for example to flag an error).
|
| Post-trapping code is entered in SVC mode, with interrupts
| disabled.
|
| If more than one client has claimed a SWI, it is the earliest
| claimant�s post-trapping code that is called first, subject
| to priority. (See footnote 2.)
|
| Remember that your post-trapping code may well be entered in an
| error condition. So check whether the V flag is set on entry,
| and return if it is (if you return with the S flag (MovS Pc,R14
| or LdmFd R13!,{...,Pc}^, the flags are unaffected). Never
| change the PSR flags by accident.
|
|
| Unlike OS_Claim, this SWI will not remove previous instances of
| claims with the same values. The release routine also only
| removes one instance of the values at a time.
|
| Claiming the Wimp_RegisterFilter SWI only traps the normal
| filter-based use of the SWI. Under no circumstances should you
| call Wimp_RegisterFilter with WimpSWIVe usage in your trapping
| code. If you really must claim or release a SWI when some other
| SWI is executed, use a CallBack to do it. (See the RISC OS 3
| Programmers� Reference Manual, page 1-319.)
|
| Don�t post-trap Wimp_Poll(Idle) or Wimp_StartTask: it�s a bad
| idea. WimpSWIVe deals with it adequately, but there are all
| sorts of simply horrid implications. Trapping Wimp_Poll is
| easy anyway, using the old filter system.
|
| And finally, don�t use the �claim all SWIs� flag unless you
| really want all the SWIs. Don�t use it for trapping a number
| of different SWIs, use many separate claims: the speed
| difference will be negligable, and you needn�t worry about
| Wimp_Poll. The �claim all SWIs� flag is unlikely to be widely
| useful - a Wimp SWI logging program seems to be the only
| possible user.
|
Errors: | Bad value passed to WIMP in R0
| if WimpSWIVe is not loaded, the attempt to use this SWI in
| the WimpSWIVe manner will cause this error
| Bad WimpSWIVe release
| releasing a SWI you had not claimed generates this error
| No room in RMA
| is also possible but highly unlikely.
|
Footnote 1 - Re-entrancy issues:
Re-entrancy is nae problem if you only use pre-trapping or only use post-
trapping - you can either be re-entrant by using a stack to store stuff, or
prevent re-entering using a threaded flag (and unless you call a SWI, you
cannot be re-entered anyway). If you use both, but the post-code always does
the same regardless of the pre-code, you�re all right too.
But if you use both at once and the action of post depends on something
that happened in pre (for example if you have pre to check the reason code
is worth bothering with in the post-trap code), it is slightly more complex.
It�s quite possible that calling a Wimp SWI may cause another Wimp SWI to be
called, especially when you consider there can be many WimpSWIVe claimants.
Consider:
SWI Wimp_Thing called
WimpSWIVe claimant 1 pre-traps SWI
Claimant 1 store data for SWI 1 in workspace
WimpSWIVe claimant 2 pre-traps SWI
Claimant 2 executes Wimp_Gubbins
Wimp_Gubbins causes Wimp_Thing to be called
WimpSWIVe claimant 1 pre-traps SWI
Claimant 1 stores data for SWI 2 in workspace
WimpSWIVe claimant 2 pre-traps SWI
Claimant 2 is threaded, and so does nothing
WimpSWIVe executes real SWI Wimp_Thing
WimpSWIVe claimant 2 post-traps SWI
Claimant 2 is threaded, and so does nothing
WimpSWIVe claimant 1 post-traps SWI
Claimant 1 performs action on results, dependent on workspace
which holds data for SWI 2
WimpSWIVe returns
WimpSWIVe executes real Wimp_Thing SWI
WimpSWIVe claimant 2 post-traps SWI
Claimant 2 does whatever it needs to with results
WimpSWIVe claimant 1 post-traps SWI
Claimant 1 performs action on results, dependent on workspace
which holds data for SWI *2*
WimpSWIVe returns
As you can see, there is a lot of scope here for things going wrong, and
horrible clashes where one WimpSWIVe program may make another go wrong,
potentially rather messily.
There are two things you can do about it. Perhaps the best is to store a
�count� of post-traps to ignore. This count should be zero initially, and
should be incremented first when your pre-trap code detects that post-
trapping should do something effective. It should also be incremented every
time the pre-trap code is entered with the count non-zero. The post trap code
then checks the count on entry. If the count is zero, it returns doing
nothing. If the count is one or greater, the count is decremented. If the
count is one exactly one, the effect of the post-trap is activated. There�s
an example of this in the EigenSysInfo source.
This is fine normally, but it makes the trapping code only affect the first
SWI to be affected (the "outermost" affected SWI). If you want to be truly
re-entrant, you�d have to store values on the stack to indicate whether to
post-trap on each call. And you couldn�t use the SVC stack, so you�d have to
use a private stack. And you�d have to revert to the above behaviour if the
stack was filled up. Therefore, I don�t reckon it�s worth bothering with,
especially as allowing true re-entrancy opens the door to recursive problems
(Wimp_Thing calls Wimp_Gubbins calls Wimp_Thing calls Wimp_Gubbins etc.) too.
Sorry about the complexity of this footnote. Relax. You don�t need to
bother about all this horrid stuff, usually. :-)
Footnote 2:
Your post-trap code will only be called if the SWI does return. This might
not happen if the SWI is one that doesn�t return (but I can�t think of any
Wimp_ SWIs that don�t), or if a serious error happens. The latter should
never happen in a perfect system, but bugs happen and the SWI being trapped
might branch through zero or something. With the Wimp, though, a crash at
this stage often means there is something very wrong with the whole desktop
and everything is going to die anyway, so your module failing to post-trap
is unlikely to annoy the user much. :-)
-----------------------------------------------------------------------------
This module is supplied with some example programs:
- 3DErrorWindow. This is a useful module that replaces the WIMP�s error
windows with its own Risc PCable 3D ones (it needs 3DErrorWindow$Path to
point to a directory containing Templates and Messages - you can find one
in Sources.ErrorWind) using pre-trapping (usually with interception). The
windows could do with the NewerLook �titlejoint� sprite in the wimp pool,
along with the Risc PC error system sprites. Note that this is an OLD
VERSION of 3DErrorWindow, which you should not actually use - get
NewerLook for the fullest, newest version. This, however, is a better
example of how to use WimpSWIVe, as it is less complicated than the
latest version.
- EigenSysInfo. This is a pretty useless one that changes Wimp_ReadSysInfo
2 always to return 24 or 22, and return the latter if Log2YEig<2 (the
WIMP returns 22 if Log2YEig==Log2XEig, which is silly). It also goes
�beep� if the Wimp returned a different value to it (try mode 22 and the
like). It�s not particularly great because most programs don�t take any
notice of ReadSysInfo (partly because of its aforementioned bobbinsness)
but it shows you how to pre-trap and post-trap SWIs at the same time (as
in footnote 1).
The source for these programs, along with the full source to WimpSWIVe and
some resources for 3DErrorWindow are to be found in the Sources directory.
However, these programs require BAX to be loaded for them to compile. BAX is
DoggySoft�s Basic Assembler Extension, which provides all ARM3, ARM6, FPA10
and coprocessor instructions, along with many useful pseudo-instructions.
You can get BAX from good PD libraries and Arcade, Digital Databank and
Furzefield Hq BBSs. It�s essential for Basic assembler programmers!
If you use this module in a program, be sure to RMEnsure version 0.04 or
later - versions 0.01 and 0.02 are NewerLook quick releases with bugs in
post-trapping, and version 0.03 does not feature high-priority SWI trapping,
as well as sometimes entering pre-code with interrupts enabled.
This module is freeware. Free free to distribute and use. To contact me -
for praise, to suggest new bits to add, or (heaven forbid) to report a bug,
please write to:
Andrew Clover,
7 Blackhorse Crescent,
Amersham,
Bucks.,
HP6 6HP.
Or phone me on 01494-431916, send a fax on 01494-675878, send some email to
ajc@doggysft.demon.co.uk or even telex on 83675 Brit G.
00000000 57 69 6d 70 53 57 49 56 65 20 20 20 20 20 20 20 |WimpSWIVe |
00000010 30 2e 30 35 20 28 33 30 20 4f 63 74 20 31 39 39 |0.05 (30 Oct 199|
00000020 35 29 0a 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d |5).=============|
00000030 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d 3d |================|
00000040 3d 3d 3d 3d 3d 0a 0a 0a 20 4e 65 77 65 72 4c 6f |=====... NewerLo|
00000050 6f 6b 20 6e 65 65 64 73 20 74 6f 20 74 72 61 70 |ok needs to trap|
00000060 20 57 69 6d 70 5f 20 53 57 49 73 20 69 6e 20 6f | Wimp_ SWIs in o|
00000070 72 64 65 72 20 74 6f 20 70 72 6f 76 69 64 65 20 |rder to provide |
00000080 69 74 73 20 6e 65 77 20 65 72 72 6f 72 0a 77 69 |its new error.wi|
00000090 6e 64 6f 77 73 2e 20 54 68 65 20 6f 6e 6c 79 20 |ndows. The only |
000000a0 6f 66 66 69 63 69 61 6c 20 77 61 79 20 74 6f 20 |official way to |
000000b0 74 72 61 70 20 53 57 49 73 20 69 73 20 74 6f 20 |trap SWIs is to |
000000c0 74 72 61 70 20 74 68 65 20 53 57 49 20 68 61 72 |trap the SWI har|
000000d0 64 77 61 72 65 0a 76 65 63 74 6f 72 2c 20 62 75 |dware.vector, bu|
000000e0 74 20 65 76 65 6e 20 74 68 69 73 20 69 73 20 6e |t even this is n|
000000f0 6f 74 20 72 65 63 6f 6d 6d 65 6e 64 65 64 2e 20 |ot recommended. |
00000100 49 74 20 74 61 6b 65 73 20 6d 75 63 68 20 63 6f |It takes much co|
00000110 64 65 20 74 6f 20 69 6d 70 6c 65 6d 65 6e 74 0a |de to implement.|
00000120 70 72 6f 70 65 72 6c 79 20 69 6e 20 2a 61 6c 6c |properly in *all|
00000130 2a 20 63 69 72 63 75 6d 73 74 61 6e 63 65 73 20 |* circumstances |
00000140 28 61 62 6f 75 74 20 33 30 4b 20 6f 66 20 73 6f |(about 30K of so|
00000150 75 72 63 65 20 63 6f 64 65 20 69 6e 20 44 65 73 |urce code in Des|
00000160 6b 74 6f 70 20 48 61 63 6b 65 72 29 2c 0a 61 6e |ktop Hacker),.an|
00000170 64 20 63 61 6e 20 73 6c 6f 77 20 74 68 65 20 6d |d can slow the m|
00000180 61 63 68 69 6e 65 20 64 6f 77 6e 2c 20 71 75 69 |achine down, qui|
00000190 74 65 20 63 6f 6e 73 69 64 65 72 61 62 6c 79 20 |te considerably |
000001a0 77 68 65 6e 20 74 68 65 72 65 20 61 72 65 20 6d |when there are m|
000001b0 75 6c 74 69 70 6c 65 0a 63 6c 61 69 6d 61 6e 74 |ultiple.claimant|
000001c0 73 2e 0a 0a 20 49 74 20 69 73 2c 20 68 6f 77 65 |s... It is, howe|
000001d0 76 65 72 2c 20 70 6f 73 73 69 62 6c 65 20 74 6f |ver, possible to|
000001e0 20 74 72 61 70 20 57 69 6d 70 5f 20 53 57 49 73 | trap Wimp_ SWIs|
000001f0 20 62 79 20 70 72 6f 76 69 64 69 6e 67 20 61 6e | by providing an|
00000200 6f 74 68 65 72 20 6d 6f 64 75 6c 65 0a 77 69 74 |other module.wit|
00000210 68 20 74 68 65 20 73 61 6d 65 20 53 57 49 20 63 |h the same SWI c|
00000220 68 75 6e 6b 20 61 6e 64 20 6e 61 6d 65 73 2e 20 |hunk and names. |
00000230 54 68 69 73 20 6d 65 74 68 6f 64 20 69 73 20 6d |This method is m|
00000240 75 63 68 20 71 75 69 63 6b 65 72 20 61 6e 64 20 |uch quicker and |
00000250 65 61 73 69 65 72 2c 0a 62 75 74 20 69 74 20 69 |easier,.but it i|
00000260 73 20 2d 20 61 73 20 49 91 6c 6c 20 68 61 70 70 |s - as I.ll happ|
00000270 69 6c 79 20 61 64 6d 69 74 20 2d 20 72 61 74 68 |ily admit - rath|
00000280 65 72 20 64 6f 64 67 79 2e 20 4f 6e 65 20 6f 66 |er dodgy. One of|
00000290 20 74 68 65 20 70 72 6f 62 6c 65 6d 73 20 69 73 | the problems is|
000002a0 0a 74 68 61 74 20 6f 6e 6c 79 20 6f 6e 65 20 6d |.that only one m|
000002b0 6f 64 75 6c 65 20 63 61 6e 20 64 6f 20 74 68 69 |odule can do thi|
000002c0 73 20 61 74 20 61 20 74 69 6d 65 2e 20 53 6f 20 |s at a time. So |
000002d0 69 66 20 4e 65 77 65 72 4c 6f 6f 6b 20 68 61 64 |if NewerLook had|
000002e0 20 61 20 6d 6f 64 75 6c 65 0a 74 68 61 74 20 75 | a module.that u|
000002f0 73 65 64 20 74 68 69 73 20 6d 65 74 68 6f 64 2c |sed this method,|
00000300 20 69 74 20 77 6f 75 6c 64 6e 91 74 20 77 6f 72 | it wouldn.t wor|
00000310 6b 20 70 72 6f 70 65 72 6c 79 20 77 68 65 6e 20 |k properly when |
00000320 61 6e 6f 74 68 65 72 20 70 72 6f 67 72 61 6d 20 |another program |
00000330 74 72 69 65 64 0a 74 6f 20 64 6f 20 74 68 65 20 |tried.to do the |
00000340 73 61 6d 65 20 74 68 69 6e 67 2e 20 28 41 6e 64 |same thing. (And|
00000350 20 79 6f 75 20 6b 6e 6f 77 20 73 6f 6d 65 20 70 | you know some p|
00000360 72 6f 67 72 61 6d 20 77 69 6c 6c 2e 29 0a 0a 20 |rogram will.).. |
00000370 54 68 75 73 2c 20 49 20 68 61 76 65 20 73 65 70 |Thus, I have sep|
00000380 61 72 61 74 65 64 20 74 68 65 20 74 72 61 70 70 |arated the trapp|
00000390 69 6e 67 20 63 6f 64 65 20 66 72 6f 6d 20 74 68 |ing code from th|
000003a0 65 20 61 63 74 69 6f 6e 20 63 6f 64 65 20 28 77 |e action code (w|
000003b0 68 69 63 68 20 72 65 73 69 64 65 73 0a 69 6e 20 |hich resides.in |
000003c0 61 6e 6f 74 68 65 72 20 6d 6f 64 75 6c 65 29 2c |another module),|
000003d0 20 61 6e 64 20 72 65 6c 65 61 73 65 64 20 74 68 | and released th|
000003e0 69 73 20 6d 6f 64 75 6c 65 20 73 65 70 61 72 61 |is module separa|
000003f0 74 65 6c 79 2e 20 49 74 20 63 61 6e 20 6d 61 6e |tely. It can man|
00000400 61 67 65 20 53 57 49 0a 63 6c 61 69 6d 73 20 61 |age SWI.claims a|
00000410 6e 64 20 72 65 6c 65 61 73 65 73 20 64 79 6e 61 |nd releases dyna|
00000420 6d 69 63 61 6c 6c 79 2c 20 61 20 62 69 74 20 6c |mically, a bit l|
00000430 69 6b 65 20 76 65 63 74 6f 72 73 2e 20 41 63 74 |ike vectors. Act|
00000440 75 61 6c 6c 79 2c 20 71 75 69 74 65 20 61 20 6c |ually, quite a l|
00000450 6f 74 0a 6c 69 6b 65 20 76 65 63 74 6f 72 73 2e |ot.like vectors.|
00000460 20 59 6f 75 20 63 61 6e 20 75 73 65 20 69 74 20 | You can use it |
00000470 69 6e 20 79 6f 75 72 20 6f 77 6e 20 70 72 6f 67 |in your own prog|
00000480 72 61 6d 73 20 69 66 20 79 6f 75 20 6c 69 6b 65 |rams if you like|
00000490 2e 20 48 65 72 65 91 73 20 68 6f 77 2e 0a 0a 20 |. Here.s how... |
000004a0 42 65 63 61 75 73 65 20 57 69 6d 70 53 57 49 56 |Because WimpSWIV|
000004b0 65 20 75 73 65 73 20 74 68 65 20 57 69 6d 70 91 |e uses the Wimp.|
000004c0 73 20 53 57 49 20 63 68 75 6e 6b 2c 20 69 74 20 |s SWI chunk, it |
000004d0 63 61 6e 6e 6f 74 20 70 72 6f 76 69 64 65 20 69 |cannot provide i|
000004e0 74 73 20 6f 77 6e 0a 53 57 49 73 2e 20 49 6e 73 |ts own.SWIs. Ins|
000004f0 74 65 61 64 2c 20 69 74 20 63 6f 6d 6d 75 6e 69 |tead, it communi|
00000500 63 61 74 65 73 20 75 73 69 6e 67 20 61 20 57 69 |cates using a Wi|
00000510 6d 70 20 53 57 49 2c 20 6e 61 6d 65 6c 79 20 57 |mp SWI, namely W|
00000520 69 6d 70 5f 52 65 67 69 73 74 65 72 46 69 6c 74 |imp_RegisterFilt|
00000530 65 72 2e 0a 48 65 72 65 20 69 73 20 74 68 65 20 |er..Here is the |
00000540 57 69 6d 70 53 57 49 56 65 20 73 70 65 63 69 66 |WimpSWIVe specif|
00000550 69 63 61 74 69 6f 6e 20 66 6f 72 20 57 69 6d 70 |ication for Wimp|
00000560 5f 52 65 67 69 73 74 65 72 46 69 6c 74 65 72 2e |_RegisterFilter.|
00000570 0a 0a 0a 20 20 20 20 20 20 20 20 20 20 20 20 7c |... ||
00000580 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | |
*
000005a0 20 20 20 20 20 20 20 20 20 20 20 20 20 57 69 6d | Wim|
000005b0 70 5f 52 65 67 69 73 74 65 72 46 69 6c 74 65 72 |p_RegisterFilter|
000005c0 0a 20 20 20 20 20 20 20 20 20 20 20 20 7c 20 20 |. | |
000005d0 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | |
*
00000600 20 20 28 53 57 49 20 26 34 30 30 46 35 29 0a 20 | (SWI &400F5). |
00000610 20 20 20 20 20 20 20 20 20 20 20 7c 0a 20 20 20 | |. |
00000620 20 20 20 20 20 20 20 20 20 7c 20 55 73 65 64 20 | | Used |
00000630 62 79 20 74 68 65 20 46 69 6c 74 65 72 20 4d 61 |by the Filter Ma|
00000640 6e 61 67 65 72 20 74 6f 20 72 65 67 69 73 74 65 |nager to registe|
00000650 72 20 6f 72 20 64 65 72 65 67 69 73 74 65 72 20 |r or deregister |
00000660 61 20 66 69 6c 74 65 72 0a 20 20 20 20 20 20 20 |a filter. |
00000670 20 20 20 20 20 7c 20 4f 52 20 75 73 65 64 20 74 | | OR used t|
00000680 6f 20 72 65 67 69 73 74 65 72 20 53 57 49 20 63 |o register SWI c|
00000690 6c 61 69 6d 73 20 61 6e 64 20 72 65 6c 65 61 73 |laims and releas|
000006a0 65 73 20 77 69 74 68 20 57 69 6d 70 53 57 49 56 |es with WimpSWIV|
000006b0 65 0a 20 20 20 20 20 20 20 20 20 20 20 20 7c 0a |e. |.|
000006c0 20 20 4f 6e 20 65 6e 74 72 79 3a 20 7c 20 52 30 | On entry: | R0|
000006d0 20 3d 20 72 65 61 73 6f 6e 20 63 6f 64 65 3a 0a | = reason code:.|
000006e0 20 20 20 20 20 20 20 20 20 20 20 20 7c 20 20 20 | | |
000006f0 20 20 20 20 20 20 26 34 39 35 37 35 33 35 37 20 | &49575357 |
00000700 28 94 57 53 57 49 95 29 20 66 6f 72 20 57 69 6d |(.WSWI.) for Wim|
00000710 70 53 57 49 56 65 20 6f 70 65 72 61 74 69 6f 6e |pSWIVe operation|
00000720 20 28 73 65 65 20 62 65 6c 6f 77 29 0a 20 20 20 | (see below). |
00000730 20 20 20 20 20 20 20 20 20 7c 20 20 20 20 20 20 | | |
00000740 20 20 20 61 6e 79 74 68 69 6e 67 20 65 6c 73 65 | anything else|
00000750 20 66 6f 72 20 66 69 6c 74 65 72 20 6f 70 65 72 | for filter oper|
00000760 61 74 69 6f 6e 20 28 73 65 65 20 52 49 53 43 20 |ation (see RISC |
00000770 4f 53 20 33 0a 20 20 20 20 20 20 20 20 20 20 20 |OS 3. |
00000780 20 7c 20 20 20 20 20 20 20 20 20 50 72 6f 67 72 | | Progr|
00000790 61 6d 6d 65 72 73 91 20 52 65 66 65 72 65 6e 63 |ammers. Referenc|
000007a0 65 20 4d 61 6e 75 61 6c 2c 20 70 61 67 65 20 33 |e Manual, page 3|
000007b0 2d 32 32 34 29 0a 20 20 20 20 20 20 20 20 20 20 |-224). |
000007c0 20 20 7c 20 52 31 20 3d 20 53 57 49 20 77 6f 72 | | R1 = SWI wor|
000007d0 64 3a 0a 20 20 20 20 20 20 20 20 20 20 20 20 7c |d:. ||
000007e0 20 20 20 20 20 20 20 20 20 62 69 74 73 20 30 2d | bits 0-|
000007f0 35 20 3a 20 6f 66 66 73 65 74 20 69 6e 20 53 57 |5 : offset in SW|
00000800 49 20 63 68 75 6e 6b 20 6f 66 20 53 57 49 20 74 |I chunk of SWI t|
00000810 6f 20 63 6c 61 69 6d 2f 72 65 6c 65 61 73 65 0a |o claim/release.|
00000820 20 20 20 20 20 20 20 20 20 20 20 20 7c 20 20 20 | | |
00000830 20 20 20 20 20 20 62 69 74 20 20 36 20 20 20 3a | bit 6 :|
00000840 20 69 67 6e 6f 72 65 20 62 69 74 73 20 30 2d 35 | ignore bits 0-5|
00000850 20 61 6e 64 20 63 6c 61 69 6d 20 61 6c 6c 20 57 | and claim all W|
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00001950 20 20 20 20 20 20 20 20 20 20 20 20 7c 20 55 6e | | Un|
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000019a0 20 20 20 20 20 20 20 20 20 20 7c 20 63 6c 61 69 | | clai|
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00001a00 20 69 6e 73 74 61 6e 63 65 20 6f 66 20 74 68 65 | instance of the|
00001a10 20 76 61 6c 75 65 73 20 61 74 20 61 20 74 69 6d | values at a tim|
00001a20 65 2e 0a 20 20 20 20 20 20 20 20 20 20 20 20 7c |e.. ||
00001a30 0a 20 20 20 20 20 20 20 20 20 20 20 20 7c 20 43 |. | C|
00001a40 6c 61 69 6d 69 6e 67 20 74 68 65 20 57 69 6d 70 |laiming the Wimp|
00001a50 5f 52 65 67 69 73 74 65 72 46 69 6c 74 65 72 20 |_RegisterFilter |
00001a60 53 57 49 20 6f 6e 6c 79 20 74 72 61 70 73 20 74 |SWI only traps t|
00001a70 68 65 20 6e 6f 72 6d 61 6c 0a 20 20 20 20 20 20 |he normal. |
00001a80 20 20 20 20 20 20 7c 20 66 69 6c 74 65 72 2d 62 | | filter-b|
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00001aa0 53 57 49 2e 20 55 6e 64 65 72 20 6e 6f 20 63 69 |SWI. Under no ci|
00001ab0 72 63 75 6d 73 74 61 6e 63 65 73 20 73 68 6f 75 |rcumstances shou|
00001ac0 6c 64 20 79 6f 75 0a 20 20 20 20 20 20 20 20 20 |ld you. |
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00001ae0 65 67 69 73 74 65 72 46 69 6c 74 65 72 20 77 69 |egisterFilter wi|
00001af0 74 68 20 57 69 6d 70 53 57 49 56 65 20 75 73 61 |th WimpSWIVe usa|
00001b00 67 65 20 69 6e 20 79 6f 75 72 20 74 72 61 70 70 |ge in your trapp|
00001b10 69 6e 67 0a 20 20 20 20 20 20 20 20 20 20 20 20 |ing. |
00001b20 7c 20 63 6f 64 65 2e 20 49 66 20 79 6f 75 20 72 || code. If you r|
00001b30 65 61 6c 6c 79 20 6d 75 73 74 20 63 6c 61 69 6d |eally must claim|
00001b40 20 6f 72 20 72 65 6c 65 61 73 65 20 61 20 53 57 | or release a SW|
00001b50 49 20 77 68 65 6e 20 73 6f 6d 65 20 6f 74 68 65 |I when some othe|
00001b60 72 0a 20 20 20 20 20 20 20 20 20 20 20 20 7c 20 |r. | |
00001b70 53 57 49 20 69 73 20 65 78 65 63 75 74 65 64 2c |SWI is executed,|
00001b80 20 75 73 65 20 61 20 43 61 6c 6c 42 61 63 6b 20 | use a CallBack |
00001b90 74 6f 20 64 6f 20 69 74 2e 20 28 53 65 65 20 74 |to do it. (See t|
00001ba0 68 65 20 52 49 53 43 20 4f 53 20 33 0a 20 20 20 |he RISC OS 3. |
00001bb0 20 20 20 20 20 20 20 20 20 7c 20 50 72 6f 67 72 | | Progr|
00001bc0 61 6d 6d 65 72 73 91 20 52 65 66 65 72 65 6e 63 |ammers. Referenc|
00001bd0 65 20 4d 61 6e 75 61 6c 2c 20 70 61 67 65 20 31 |e Manual, page 1|
00001be0 2d 33 31 39 2e 29 0a 20 20 20 20 20 20 20 20 20 |-319.). |
00001bf0 20 20 20 7c 0a 20 20 20 20 20 20 20 20 20 20 20 | |. |
00001c00 20 7c 20 44 6f 6e 91 74 20 70 6f 73 74 2d 74 72 | | Don.t post-tr|
00001c10 61 70 20 57 69 6d 70 5f 50 6f 6c 6c 28 49 64 6c |ap Wimp_Poll(Idl|
00001c20 65 29 20 6f 72 20 57 69 6d 70 5f 53 74 61 72 74 |e) or Wimp_Start|
00001c30 54 61 73 6b 3a 20 69 74 91 73 20 61 20 62 61 64 |Task: it.s a bad|
00001c40 0a 20 20 20 20 20 20 20 20 20 20 20 20 7c 20 69 |. | i|
00001c50 64 65 61 2e 20 57 69 6d 70 53 57 49 56 65 20 64 |dea. WimpSWIVe d|
00001c60 65 61 6c 73 20 77 69 74 68 20 69 74 20 61 64 65 |eals with it ade|
00001c70 71 75 61 74 65 6c 79 2c 20 62 75 74 20 74 68 65 |quately, but the|
00001c80 72 65 20 61 72 65 20 61 6c 6c 0a 20 20 20 20 20 |re are all. |
00001c90 20 20 20 20 20 20 20 7c 20 73 6f 72 74 73 20 6f | | sorts o|
00001ca0 66 20 73 69 6d 70 6c 79 20 68 6f 72 72 69 64 20 |f simply horrid |
00001cb0 69 6d 70 6c 69 63 61 74 69 6f 6e 73 2e 20 54 72 |implications. Tr|
00001cc0 61 70 70 69 6e 67 20 57 69 6d 70 5f 50 6f 6c 6c |apping Wimp_Poll|
00001cd0 20 69 73 0a 20 20 20 20 20 20 20 20 20 20 20 20 | is. |
00001ce0 7c 20 65 61 73 79 20 61 6e 79 77 61 79 2c 20 75 || easy anyway, u|
00001cf0 73 69 6e 67 20 74 68 65 20 6f 6c 64 20 66 69 6c |sing the old fil|
00001d00 74 65 72 20 73 79 73 74 65 6d 2e 0a 20 20 20 20 |ter system.. |
00001d10 20 20 20 20 20 20 20 20 7c 0a 20 20 20 20 20 20 | |. |
00001d20 20 20 20 20 20 20 7c 20 41 6e 64 20 66 69 6e 61 | | And fina|
00001d30 6c 6c 79 2c 20 64 6f 6e 91 74 20 75 73 65 20 74 |lly, don.t use t|
00001d40 68 65 20 90 63 6c 61 69 6d 20 61 6c 6c 20 53 57 |he .claim all SW|
00001d50 49 73 91 20 66 6c 61 67 20 75 6e 6c 65 73 73 20 |Is. flag unless |
00001d60 79 6f 75 0a 20 20 20 20 20 20 20 20 20 20 20 20 |you. |
00001d70 7c 20 72 65 61 6c 6c 79 20 77 61 6e 74 20 61 6c || really want al|
00001d80 6c 20 74 68 65 20 53 57 49 73 2e 20 44 6f 6e 91 |l the SWIs. Don.|
00001d90 74 20 75 73 65 20 69 74 20 66 6f 72 20 74 72 61 |t use it for tra|
00001da0 70 70 69 6e 67 20 61 20 6e 75 6d 62 65 72 0a 20 |pping a number. |
00001db0 20 20 20 20 20 20 20 20 20 20 20 7c 20 6f 66 20 | | of |
00001dc0 64 69 66 66 65 72 65 6e 74 20 53 57 49 73 2c 20 |different SWIs, |
00001dd0 75 73 65 20 6d 61 6e 79 20 73 65 70 61 72 61 74 |use many separat|
00001de0 65 20 63 6c 61 69 6d 73 3a 20 74 68 65 20 73 70 |e claims: the sp|
00001df0 65 65 64 0a 20 20 20 20 20 20 20 20 20 20 20 20 |eed. |
00001e00 7c 20 64 69 66 66 65 72 65 6e 63 65 20 77 69 6c || difference wil|
00001e10 6c 20 62 65 20 6e 65 67 6c 69 67 61 62 6c 65 2c |l be negligable,|
00001e20 20 61 6e 64 20 79 6f 75 20 6e 65 65 64 6e 91 74 | and you needn.t|
00001e30 20 77 6f 72 72 79 20 61 62 6f 75 74 0a 20 20 20 | worry about. |
00001e40 20 20 20 20 20 20 20 20 20 7c 20 57 69 6d 70 5f | | Wimp_|
00001e50 50 6f 6c 6c 2e 20 54 68 65 20 90 63 6c 61 69 6d |Poll. The .claim|
00001e60 20 61 6c 6c 20 53 57 49 73 91 20 66 6c 61 67 20 | all SWIs. flag |
00001e70 69 73 20 75 6e 6c 69 6b 65 6c 79 20 74 6f 20 62 |is unlikely to b|
00001e80 65 20 77 69 64 65 6c 79 0a 20 20 20 20 20 20 20 |e widely. |
00001e90 20 20 20 20 20 7c 20 75 73 65 66 75 6c 20 2d 20 | | useful - |
00001ea0 61 20 57 69 6d 70 20 53 57 49 20 6c 6f 67 67 69 |a Wimp SWI loggi|
00001eb0 6e 67 20 70 72 6f 67 72 61 6d 20 73 65 65 6d 73 |ng program seems|
00001ec0 20 74 6f 20 62 65 20 74 68 65 20 6f 6e 6c 79 0a | to be the only.|
00001ed0 20 20 20 20 20 20 20 20 20 20 20 20 7c 20 70 6f | | po|
00001ee0 73 73 69 62 6c 65 20 75 73 65 72 2e 0a 20 20 20 |ssible user.. |
00001ef0 20 20 20 20 20 20 20 20 20 7c 0a 20 20 20 20 45 | |. E|
00001f00 72 72 6f 72 73 3a 20 7c 20 42 61 64 20 76 61 6c |rrors: | Bad val|
00001f10 75 65 20 70 61 73 73 65 64 20 74 6f 20 57 49 4d |ue passed to WIM|
00001f20 50 20 69 6e 20 52 30 0a 20 20 20 20 20 20 20 20 |P in R0. |
00001f30 20 20 20 20 7c 20 20 20 20 69 66 20 57 69 6d 70 | | if Wimp|
00001f40 53 57 49 56 65 20 69 73 20 6e 6f 74 20 6c 6f 61 |SWIVe is not loa|
00001f50 64 65 64 2c 20 74 68 65 20 61 74 74 65 6d 70 74 |ded, the attempt|
00001f60 20 74 6f 20 75 73 65 20 74 68 69 73 20 53 57 49 | to use this SWI|
00001f70 20 69 6e 0a 20 20 20 20 20 20 20 20 20 20 20 20 | in. |
00001f80 7c 20 20 20 20 74 68 65 20 57 69 6d 70 53 57 49 || the WimpSWI|
00001f90 56 65 20 6d 61 6e 6e 65 72 20 77 69 6c 6c 20 63 |Ve manner will c|
00001fa0 61 75 73 65 20 74 68 69 73 20 65 72 72 6f 72 0a |ause this error.|
00001fb0 20 20 20 20 20 20 20 20 20 20 20 20 7c 20 42 61 | | Ba|
00001fc0 64 20 57 69 6d 70 53 57 49 56 65 20 72 65 6c 65 |d WimpSWIVe rele|
00001fd0 61 73 65 0a 20 20 20 20 20 20 20 20 20 20 20 20 |ase. |
00001fe0 7c 20 20 20 20 72 65 6c 65 61 73 69 6e 67 20 61 || releasing a|
00001ff0 20 53 57 49 20 79 6f 75 20 68 61 64 20 6e 6f 74 | SWI you had not|
00002000 20 63 6c 61 69 6d 65 64 20 67 65 6e 65 72 61 74 | claimed generat|
00002010 65 73 20 74 68 69 73 20 65 72 72 6f 72 0a 20 20 |es this error. |
00002020 20 20 20 20 20 20 20 20 20 20 7c 20 4e 6f 20 72 | | No r|
00002030 6f 6f 6d 20 69 6e 20 52 4d 41 0a 20 20 20 20 20 |oom in RMA. |
00002040 20 20 20 20 20 20 20 7c 20 20 20 20 69 73 20 61 | | is a|
00002050 6c 73 6f 20 70 6f 73 73 69 62 6c 65 20 62 75 74 |lso possible but|
00002060 20 68 69 67 68 6c 79 20 75 6e 6c 69 6b 65 6c 79 | highly unlikely|
00002070 2e 0a 20 20 20 20 20 20 20 20 20 20 20 20 7c 0a |.. |.|
00002080 0a 0a 20 46 6f 6f 74 6e 6f 74 65 20 31 20 2d 20 |.. Footnote 1 - |
00002090 52 65 2d 65 6e 74 72 61 6e 63 79 20 69 73 73 75 |Re-entrancy issu|
000020a0 65 73 3a 0a 0a 20 52 65 2d 65 6e 74 72 61 6e 63 |es:.. Re-entranc|
000020b0 79 20 69 73 20 6e 61 65 20 70 72 6f 62 6c 65 6d |y is nae problem|
000020c0 20 69 66 20 79 6f 75 20 6f 6e 6c 79 20 75 73 65 | if you only use|
000020d0 20 70 72 65 2d 74 72 61 70 70 69 6e 67 20 6f 72 | pre-trapping or|
000020e0 20 6f 6e 6c 79 20 75 73 65 20 70 6f 73 74 2d 0a | only use post-.|
000020f0 74 72 61 70 70 69 6e 67 20 2d 20 79 6f 75 20 63 |trapping - you c|
00002100 61 6e 20 65 69 74 68 65 72 20 62 65 20 72 65 2d |an either be re-|
00002110 65 6e 74 72 61 6e 74 20 62 79 20 75 73 69 6e 67 |entrant by using|
00002120 20 61 20 73 74 61 63 6b 20 74 6f 20 73 74 6f 72 | a stack to stor|
00002130 65 20 73 74 75 66 66 2c 20 6f 72 0a 70 72 65 76 |e stuff, or.prev|
00002140 65 6e 74 20 72 65 2d 65 6e 74 65 72 69 6e 67 20 |ent re-entering |
00002150 75 73 69 6e 67 20 61 20 74 68 72 65 61 64 65 64 |using a threaded|
00002160 20 66 6c 61 67 20 28 61 6e 64 20 75 6e 6c 65 73 | flag (and unles|
00002170 73 20 79 6f 75 20 63 61 6c 6c 20 61 20 53 57 49 |s you call a SWI|
00002180 2c 20 79 6f 75 0a 63 61 6e 6e 6f 74 20 62 65 20 |, you.cannot be |
00002190 72 65 2d 65 6e 74 65 72 65 64 20 61 6e 79 77 61 |re-entered anywa|
000021a0 79 29 2e 20 49 66 20 79 6f 75 20 75 73 65 20 62 |y). If you use b|
000021b0 6f 74 68 2c 20 62 75 74 20 74 68 65 20 70 6f 73 |oth, but the pos|
000021c0 74 2d 63 6f 64 65 20 61 6c 77 61 79 73 20 64 6f |t-code always do|
000021d0 65 73 0a 74 68 65 20 73 61 6d 65 20 72 65 67 61 |es.the same rega|
000021e0 72 64 6c 65 73 73 20 6f 66 20 74 68 65 20 70 72 |rdless of the pr|
000021f0 65 2d 63 6f 64 65 2c 20 79 6f 75 91 72 65 20 61 |e-code, you.re a|
00002200 6c 6c 20 72 69 67 68 74 20 74 6f 6f 2e 0a 0a 20 |ll right too... |
00002210 42 75 74 20 69 66 20 79 6f 75 20 75 73 65 20 62 |But if you use b|
00002220 6f 74 68 20 61 74 20 6f 6e 63 65 20 61 6e 64 20 |oth at once and |
00002230 74 68 65 20 61 63 74 69 6f 6e 20 6f 66 20 70 6f |the action of po|
00002240 73 74 20 64 65 70 65 6e 64 73 20 6f 6e 20 73 6f |st depends on so|
00002250 6d 65 74 68 69 6e 67 0a 74 68 61 74 20 68 61 70 |mething.that hap|
00002260 70 65 6e 65 64 20 69 6e 20 70 72 65 20 28 66 6f |pened in pre (fo|
00002270 72 20 65 78 61 6d 70 6c 65 20 69 66 20 79 6f 75 |r example if you|
00002280 20 68 61 76 65 20 70 72 65 20 74 6f 20 63 68 65 | have pre to che|
00002290 63 6b 20 74 68 65 20 72 65 61 73 6f 6e 20 63 6f |ck the reason co|
000022a0 64 65 0a 69 73 20 77 6f 72 74 68 20 62 6f 74 68 |de.is worth both|
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000022c0 65 20 70 6f 73 74 2d 74 72 61 70 20 63 6f 64 65 |e post-trap code|
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000022e0 79 20 6d 6f 72 65 20 63 6f 6d 70 6c 65 78 2e 0a |y more complex..|
000022f0 49 74 91 73 20 71 75 69 74 65 20 70 6f 73 73 69 |It.s quite possi|
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00002320 63 61 75 73 65 20 61 6e 6f 74 68 65 72 20 57 69 |cause another Wi|
00002330 6d 70 20 53 57 49 20 74 6f 20 62 65 0a 63 61 6c |mp SWI to be.cal|
00002340 6c 65 64 2c 20 65 73 70 65 63 69 61 6c 6c 79 20 |led, especially |
00002350 77 68 65 6e 20 79 6f 75 20 63 6f 6e 73 69 64 65 |when you conside|
00002360 72 20 74 68 65 72 65 20 63 61 6e 20 62 65 20 6d |r there can be m|
00002370 61 6e 79 20 57 69 6d 70 53 57 49 56 65 20 63 6c |any WimpSWIVe cl|
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000023a0 70 5f 54 68 69 6e 67 20 63 61 6c 6c 65 64 0a 20 |p_Thing called. |
000023b0 20 20 20 20 20 20 57 69 6d 70 53 57 49 56 65 20 | WimpSWIVe |
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000023d0 72 61 70 73 20 53 57 49 0a 20 20 20 20 20 20 20 |raps SWI. |
000023e0 20 20 43 6c 61 69 6d 61 6e 74 20 31 20 73 74 6f | Claimant 1 sto|
000023f0 72 65 20 64 61 74 61 20 66 6f 72 20 53 57 49 20 |re data for SWI |
00002400 31 20 69 6e 20 77 6f 72 6b 73 70 61 63 65 0a 20 |1 in workspace. |
00002410 20 20 20 20 20 20 57 69 6d 70 53 57 49 56 65 20 | WimpSWIVe |
00002420 63 6c 61 69 6d 61 6e 74 20 32 20 70 72 65 2d 74 |claimant 2 pre-t|
00002430 72 61 70 73 20 53 57 49 0a 20 20 20 20 20 20 20 |raps SWI. |
00002440 20 20 43 6c 61 69 6d 61 6e 74 20 32 20 65 78 65 | Claimant 2 exe|
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00002460 6e 73 0a 20 20 20 20 20 20 20 20 20 20 20 57 69 |ns. Wi|
00002470 6d 70 5f 47 75 62 62 69 6e 73 20 63 61 75 73 65 |mp_Gubbins cause|
00002480 73 20 57 69 6d 70 5f 54 68 69 6e 67 20 74 6f 20 |s Wimp_Thing to |
00002490 62 65 20 63 61 6c 6c 65 64 0a 20 20 20 20 20 20 |be called. |
000024a0 20 20 20 20 20 20 20 57 69 6d 70 53 57 49 56 65 | WimpSWIVe|
000024b0 20 63 6c 61 69 6d 61 6e 74 20 31 20 70 72 65 2d | claimant 1 pre-|
000024c0 74 72 61 70 73 20 53 57 49 0a 20 20 20 20 20 20 |traps SWI. |
000024d0 20 20 20 20 20 20 20 20 20 43 6c 61 69 6d 61 6e | Claiman|
000024e0 74 20 31 20 73 74 6f 72 65 73 20 64 61 74 61 20 |t 1 stores data |
000024f0 66 6f 72 20 53 57 49 20 32 20 69 6e 20 77 6f 72 |for SWI 2 in wor|
00002500 6b 73 70 61 63 65 0a 20 20 20 20 20 20 20 20 20 |kspace. |
00002510 20 20 20 20 57 69 6d 70 53 57 49 56 65 20 63 6c | WimpSWIVe cl|
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00002530 70 73 20 53 57 49 0a 20 20 20 20 20 20 20 20 20 |ps SWI. |
00002540 20 20 20 20 20 20 43 6c 61 69 6d 61 6e 74 20 32 | Claimant 2|
00002550 20 69 73 20 74 68 72 65 61 64 65 64 2c 20 61 6e | is threaded, an|
00002560 64 20 73 6f 20 64 6f 65 73 20 6e 6f 74 68 69 6e |d so does nothin|
00002570 67 0a 20 20 20 20 20 20 20 20 20 20 20 20 20 57 |g. W|
00002580 69 6d 70 53 57 49 56 65 20 65 78 65 63 75 74 65 |impSWIVe execute|
00002590 73 20 72 65 61 6c 20 53 57 49 20 57 69 6d 70 5f |s real SWI Wimp_|
000025a0 54 68 69 6e 67 0a 20 20 20 20 20 20 20 20 20 20 |Thing. |
000025b0 20 20 20 57 69 6d 70 53 57 49 56 65 20 63 6c 61 | WimpSWIVe cla|
000025c0 69 6d 61 6e 74 20 32 20 70 6f 73 74 2d 74 72 61 |imant 2 post-tra|
000025d0 70 73 20 53 57 49 0a 20 20 20 20 20 20 20 20 20 |ps SWI. |
000025e0 20 20 20 20 20 20 43 6c 61 69 6d 61 6e 74 20 32 | Claimant 2|
000025f0 20 69 73 20 74 68 72 65 61 64 65 64 2c 20 61 6e | is threaded, an|
00002600 64 20 73 6f 20 64 6f 65 73 20 6e 6f 74 68 69 6e |d so does nothin|
00002610 67 0a 20 20 20 20 20 20 20 20 20 20 20 20 20 57 |g. W|
00002620 69 6d 70 53 57 49 56 65 20 63 6c 61 69 6d 61 6e |impSWIVe claiman|
00002630 74 20 31 20 70 6f 73 74 2d 74 72 61 70 73 20 53 |t 1 post-traps S|
00002640 57 49 0a 20 20 20 20 20 20 20 20 20 20 20 20 20 |WI. |
00002650 20 20 43 6c 61 69 6d 61 6e 74 20 31 20 70 65 72 | Claimant 1 per|
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00002670 72 65 73 75 6c 74 73 2c 20 64 65 70 65 6e 64 65 |results, depende|
00002680 6e 74 20 6f 6e 20 77 6f 72 6b 73 70 61 63 65 0a |nt on workspace.|
00002690 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 77 | w|
000026a0 68 69 63 68 20 68 6f 6c 64 73 20 64 61 74 61 20 |hich holds data |
000026b0 66 6f 72 20 53 57 49 20 32 0a 20 20 20 20 20 20 |for SWI 2. |
000026c0 20 20 20 20 20 20 20 57 69 6d 70 53 57 49 56 65 | WimpSWIVe|
000026d0 20 72 65 74 75 72 6e 73 0a 20 20 20 20 20 20 20 | returns. |
000026e0 57 69 6d 70 53 57 49 56 65 20 65 78 65 63 75 74 |WimpSWIVe execut|
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00002710 6d 70 53 57 49 56 65 20 63 6c 61 69 6d 61 6e 74 |mpSWIVe claimant|
00002720 20 32 20 70 6f 73 74 2d 74 72 61 70 73 20 53 57 | 2 post-traps SW|
00002730 49 0a 20 20 20 20 20 20 20 20 20 43 6c 61 69 6d |I. Claim|
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00002760 77 69 74 68 20 72 65 73 75 6c 74 73 0a 20 20 20 |with results. |
00002770 20 20 20 20 57 69 6d 70 53 57 49 56 65 20 63 6c | WimpSWIVe cl|
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000027a0 20 43 6c 61 69 6d 61 6e 74 20 31 20 70 65 72 66 | Claimant 1 perf|
000027b0 6f 72 6d 73 20 61 63 74 69 6f 6e 20 6f 6e 20 72 |orms action on r|
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000027e0 20 20 20 20 20 20 20 20 77 68 69 63 68 20 68 6f | which ho|
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00002800 20 2a 32 2a 0a 20 20 20 20 20 20 20 57 69 6d 70 | *2*. Wimp|
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00002820 41 73 20 79 6f 75 20 63 61 6e 20 73 65 65 2c 20 |As you can see, |
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000028b0 0a 70 6f 74 65 6e 74 69 61 6c 6c 79 20 72 61 74 |.potentially rat|
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000028f0 62 6f 75 74 20 69 74 2e 20 50 65 72 68 61 70 73 |bout it. Perhaps|
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00002920 6f 66 20 70 6f 73 74 2d 74 72 61 70 73 20 74 6f |of post-traps to|
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00002970 65 6d 65 6e 74 65 64 20 66 69 72 73 74 20 77 68 |emented first wh|
00002980 65 6e 20 79 6f 75 72 20 70 72 65 2d 74 72 61 70 |en your pre-trap|
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000029c0 74 68 69 6e 67 20 65 66 66 65 63 74 69 76 65 2e |thing effective.|
000029d0 20 49 74 20 73 68 6f 75 6c 64 20 61 6c 73 6f 20 | It should also |
000029e0 62 65 20 69 6e 63 72 65 6d 65 6e 74 65 64 20 65 |be incremented e|
000029f0 76 65 72 79 0a 74 69 6d 65 20 74 68 65 20 70 72 |very.time the pr|
00002a00 65 2d 74 72 61 70 20 63 6f 64 65 20 69 73 20 65 |e-trap code is e|
00002a10 6e 74 65 72 65 64 20 77 69 74 68 20 74 68 65 20 |ntered with the |
00002a20 63 6f 75 6e 74 20 6e 6f 6e 2d 7a 65 72 6f 2e 20 |count non-zero. |
00002a30 54 68 65 20 70 6f 73 74 20 74 72 61 70 20 63 6f |The post trap co|
00002a40 64 65 0a 74 68 65 6e 20 63 68 65 63 6b 73 20 74 |de.then checks t|
00002a50 68 65 20 63 6f 75 6e 74 20 6f 6e 20 65 6e 74 72 |he count on entr|
00002a60 79 2e 20 49 66 20 74 68 65 20 63 6f 75 6e 74 20 |y. If the count |
00002a70 69 73 20 7a 65 72 6f 2c 20 69 74 20 72 65 74 75 |is zero, it retu|
00002a80 72 6e 73 20 64 6f 69 6e 67 0a 6e 6f 74 68 69 6e |rns doing.nothin|
00002a90 67 2e 20 49 66 20 74 68 65 20 63 6f 75 6e 74 20 |g. If the count |
00002aa0 69 73 20 6f 6e 65 20 6f 72 20 67 72 65 61 74 65 |is one or greate|
00002ab0 72 2c 20 74 68 65 20 63 6f 75 6e 74 20 69 73 20 |r, the count is |
00002ac0 64 65 63 72 65 6d 65 6e 74 65 64 2e 20 49 66 20 |decremented. If |
00002ad0 74 68 65 0a 63 6f 75 6e 74 20 69 73 20 6f 6e 65 |the.count is one|
00002ae0 20 65 78 61 63 74 6c 79 20 6f 6e 65 2c 20 74 68 | exactly one, th|
00002af0 65 20 65 66 66 65 63 74 20 6f 66 20 74 68 65 20 |e effect of the |
00002b00 70 6f 73 74 2d 74 72 61 70 20 69 73 20 61 63 74 |post-trap is act|
00002b10 69 76 61 74 65 64 2e 20 54 68 65 72 65 91 73 0a |ivated. There.s.|
00002b20 61 6e 20 65 78 61 6d 70 6c 65 20 6f 66 20 74 68 |an example of th|
00002b30 69 73 20 69 6e 20 74 68 65 20 45 69 67 65 6e 53 |is in the EigenS|
00002b40 79 73 49 6e 66 6f 20 73 6f 75 72 63 65 2e 0a 0a |ysInfo source...|
00002b50 20 54 68 69 73 20 69 73 20 66 69 6e 65 20 6e 6f | This is fine no|
00002b60 72 6d 61 6c 6c 79 2c 20 62 75 74 20 69 74 20 6d |rmally, but it m|
00002b70 61 6b 65 73 20 74 68 65 20 74 72 61 70 70 69 6e |akes the trappin|
00002b80 67 20 63 6f 64 65 20 6f 6e 6c 79 20 61 66 66 65 |g code only affe|
00002b90 63 74 20 74 68 65 20 66 69 72 73 74 0a 53 57 49 |ct the first.SWI|
00002ba0 20 74 6f 20 62 65 20 61 66 66 65 63 74 65 64 20 | to be affected |
00002bb0 28 74 68 65 20 22 6f 75 74 65 72 6d 6f 73 74 22 |(the "outermost"|
00002bc0 20 61 66 66 65 63 74 65 64 20 53 57 49 29 2e 20 | affected SWI). |
00002bd0 49 66 20 79 6f 75 20 77 61 6e 74 20 74 6f 20 62 |If you want to b|
00002be0 65 20 74 72 75 6c 79 0a 72 65 2d 65 6e 74 72 61 |e truly.re-entra|
00002bf0 6e 74 2c 20 79 6f 75 91 64 20 68 61 76 65 20 74 |nt, you.d have t|
00002c00 6f 20 73 74 6f 72 65 20 76 61 6c 75 65 73 20 6f |o store values o|
00002c10 6e 20 74 68 65 20 73 74 61 63 6b 20 74 6f 20 69 |n the stack to i|
00002c20 6e 64 69 63 61 74 65 20 77 68 65 74 68 65 72 20 |ndicate whether |
00002c30 74 6f 0a 70 6f 73 74 2d 74 72 61 70 20 6f 6e 20 |to.post-trap on |
00002c40 65 61 63 68 20 63 61 6c 6c 2e 20 41 6e 64 20 79 |each call. And y|
00002c50 6f 75 20 63 6f 75 6c 64 6e 91 74 20 75 73 65 20 |ou couldn.t use |
00002c60 74 68 65 20 53 56 43 20 73 74 61 63 6b 2c 20 73 |the SVC stack, s|
00002c70 6f 20 79 6f 75 91 64 20 68 61 76 65 20 74 6f 0a |o you.d have to.|
00002c80 75 73 65 20 61 20 70 72 69 76 61 74 65 20 73 74 |use a private st|
00002c90 61 63 6b 2e 20 41 6e 64 20 79 6f 75 91 64 20 68 |ack. And you.d h|
00002ca0 61 76 65 20 74 6f 20 72 65 76 65 72 74 20 74 6f |ave to revert to|
00002cb0 20 74 68 65 20 61 62 6f 76 65 20 62 65 68 61 76 | the above behav|
00002cc0 69 6f 75 72 20 69 66 20 74 68 65 0a 73 74 61 63 |iour if the.stac|
00002cd0 6b 20 77 61 73 20 66 69 6c 6c 65 64 20 75 70 2e |k was filled up.|
00002ce0 20 54 68 65 72 65 66 6f 72 65 2c 20 49 20 64 6f | Therefore, I do|
00002cf0 6e 91 74 20 72 65 63 6b 6f 6e 20 69 74 91 73 20 |n.t reckon it.s |
00002d00 77 6f 72 74 68 20 62 6f 74 68 65 72 69 6e 67 20 |worth bothering |
00002d10 77 69 74 68 2c 0a 65 73 70 65 63 69 61 6c 6c 79 |with,.especially|
00002d20 20 61 73 20 61 6c 6c 6f 77 69 6e 67 20 74 72 75 | as allowing tru|
00002d30 65 20 72 65 2d 65 6e 74 72 61 6e 63 79 20 6f 70 |e re-entrancy op|
00002d40 65 6e 73 20 74 68 65 20 64 6f 6f 72 20 74 6f 20 |ens the door to |
00002d50 72 65 63 75 72 73 69 76 65 20 70 72 6f 62 6c 65 |recursive proble|
00002d60 6d 73 0a 28 57 69 6d 70 5f 54 68 69 6e 67 20 63 |ms.(Wimp_Thing c|
00002d70 61 6c 6c 73 20 57 69 6d 70 5f 47 75 62 62 69 6e |alls Wimp_Gubbin|
00002d80 73 20 63 61 6c 6c 73 20 57 69 6d 70 5f 54 68 69 |s calls Wimp_Thi|
00002d90 6e 67 20 63 61 6c 6c 73 20 57 69 6d 70 5f 47 75 |ng calls Wimp_Gu|
00002da0 62 62 69 6e 73 20 65 74 63 2e 29 20 74 6f 6f 2e |bbins etc.) too.|
00002db0 0a 0a 20 53 6f 72 72 79 20 61 62 6f 75 74 20 74 |.. Sorry about t|
00002dc0 68 65 20 63 6f 6d 70 6c 65 78 69 74 79 20 6f 66 |he complexity of|
00002dd0 20 74 68 69 73 20 66 6f 6f 74 6e 6f 74 65 2e 20 | this footnote. |
00002de0 52 65 6c 61 78 2e 20 59 6f 75 20 64 6f 6e 91 74 |Relax. You don.t|
00002df0 20 6e 65 65 64 20 74 6f 0a 62 6f 74 68 65 72 20 | need to.bother |
00002e00 61 62 6f 75 74 20 61 6c 6c 20 74 68 69 73 20 68 |about all this h|
00002e10 6f 72 72 69 64 20 73 74 75 66 66 2c 20 75 73 75 |orrid stuff, usu|
00002e20 61 6c 6c 79 2e 20 3a 2d 29 0a 0a 0a 20 46 6f 6f |ally. :-)... Foo|
00002e30 74 6e 6f 74 65 20 32 3a 0a 0a 20 59 6f 75 72 20 |tnote 2:.. Your |
00002e40 70 6f 73 74 2d 74 72 61 70 20 63 6f 64 65 20 77 |post-trap code w|
00002e50 69 6c 6c 20 6f 6e 6c 79 20 62 65 20 63 61 6c 6c |ill only be call|
00002e60 65 64 20 69 66 20 74 68 65 20 53 57 49 20 64 6f |ed if the SWI do|
00002e70 65 73 20 72 65 74 75 72 6e 2e 20 54 68 69 73 20 |es return. This |
00002e80 6d 69 67 68 74 0a 6e 6f 74 20 68 61 70 70 65 6e |might.not happen|
00002e90 20 69 66 20 74 68 65 20 53 57 49 20 69 73 20 6f | if the SWI is o|
00002ea0 6e 65 20 74 68 61 74 20 64 6f 65 73 6e 91 74 20 |ne that doesn.t |
00002eb0 72 65 74 75 72 6e 20 28 62 75 74 20 49 20 63 61 |return (but I ca|
00002ec0 6e 91 74 20 74 68 69 6e 6b 20 6f 66 20 61 6e 79 |n.t think of any|
00002ed0 0a 57 69 6d 70 5f 20 53 57 49 73 20 74 68 61 74 |.Wimp_ SWIs that|
00002ee0 20 64 6f 6e 91 74 29 2c 20 6f 72 20 69 66 20 61 | don.t), or if a|
00002ef0 20 73 65 72 69 6f 75 73 20 65 72 72 6f 72 20 68 | serious error h|
00002f00 61 70 70 65 6e 73 2e 20 54 68 65 20 6c 61 74 74 |appens. The latt|
00002f10 65 72 20 73 68 6f 75 6c 64 0a 6e 65 76 65 72 20 |er should.never |
00002f20 68 61 70 70 65 6e 20 69 6e 20 61 20 70 65 72 66 |happen in a perf|
00002f30 65 63 74 20 73 79 73 74 65 6d 2c 20 62 75 74 20 |ect system, but |
00002f40 62 75 67 73 20 68 61 70 70 65 6e 20 61 6e 64 20 |bugs happen and |
00002f50 74 68 65 20 53 57 49 20 62 65 69 6e 67 20 74 72 |the SWI being tr|
00002f60 61 70 70 65 64 0a 6d 69 67 68 74 20 62 72 61 6e |apped.might bran|
00002f70 63 68 20 74 68 72 6f 75 67 68 20 7a 65 72 6f 20 |ch through zero |
00002f80 6f 72 20 73 6f 6d 65 74 68 69 6e 67 2e 20 57 69 |or something. Wi|
00002f90 74 68 20 74 68 65 20 57 69 6d 70 2c 20 74 68 6f |th the Wimp, tho|
00002fa0 75 67 68 2c 20 61 20 63 72 61 73 68 20 61 74 0a |ugh, a crash at.|
00002fb0 74 68 69 73 20 73 74 61 67 65 20 6f 66 74 65 6e |this stage often|
00002fc0 20 6d 65 61 6e 73 20 74 68 65 72 65 20 69 73 20 | means there is |
00002fd0 73 6f 6d 65 74 68 69 6e 67 20 76 65 72 79 20 77 |something very w|
00002fe0 72 6f 6e 67 20 77 69 74 68 20 74 68 65 20 77 68 |rong with the wh|
00002ff0 6f 6c 65 20 64 65 73 6b 74 6f 70 0a 61 6e 64 20 |ole desktop.and |
00003000 65 76 65 72 79 74 68 69 6e 67 20 69 73 20 67 6f |everything is go|
00003010 69 6e 67 20 74 6f 20 64 69 65 20 61 6e 79 77 61 |ing to die anywa|
00003020 79 2c 20 73 6f 20 79 6f 75 72 20 6d 6f 64 75 6c |y, so your modul|
00003030 65 20 66 61 69 6c 69 6e 67 20 74 6f 20 70 6f 73 |e failing to pos|
00003040 74 2d 74 72 61 70 0a 69 73 20 75 6e 6c 69 6b 65 |t-trap.is unlike|
00003050 6c 79 20 74 6f 20 61 6e 6e 6f 79 20 74 68 65 20 |ly to annoy the |
00003060 75 73 65 72 20 6d 75 63 68 2e 20 3a 2d 29 0a 0a |user much. :-)..|
00003070 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d |----------------|
*
000030b0 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 2d 0a 0a 20 |-------------.. |
000030c0 54 68 69 73 20 6d 6f 64 75 6c 65 20 69 73 20 73 |This module is s|
000030d0 75 70 70 6c 69 65 64 20 77 69 74 68 20 73 6f 6d |upplied with som|
000030e0 65 20 65 78 61 6d 70 6c 65 20 70 72 6f 67 72 61 |e example progra|
000030f0 6d 73 3a 0a 0a 20 2d 20 33 44 45 72 72 6f 72 57 |ms:.. - 3DErrorW|
00003100 69 6e 64 6f 77 2e 20 54 68 69 73 20 69 73 20 61 |indow. This is a|
00003110 20 75 73 65 66 75 6c 20 6d 6f 64 75 6c 65 20 74 | useful module t|
00003120 68 61 74 20 72 65 70 6c 61 63 65 73 20 74 68 65 |hat replaces the|
00003130 20 57 49 4d 50 91 73 20 65 72 72 6f 72 0a 20 20 | WIMP.s error. |
00003140 20 77 69 6e 64 6f 77 73 20 77 69 74 68 20 69 74 | windows with it|
00003150 73 20 6f 77 6e 20 52 69 73 63 20 50 43 61 62 6c |s own Risc PCabl|
00003160 65 20 33 44 20 6f 6e 65 73 20 28 69 74 20 6e 65 |e 3D ones (it ne|
00003170 65 64 73 20 33 44 45 72 72 6f 72 57 69 6e 64 6f |eds 3DErrorWindo|
00003180 77 24 50 61 74 68 20 74 6f 0a 20 20 20 70 6f 69 |w$Path to. poi|
00003190 6e 74 20 74 6f 20 61 20 64 69 72 65 63 74 6f 72 |nt to a director|
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000031b0 70 6c 61 74 65 73 20 61 6e 64 20 4d 65 73 73 61 |plates and Messa|
000031c0 67 65 73 20 2d 20 79 6f 75 20 63 61 6e 20 66 69 |ges - you can fi|
000031d0 6e 64 20 6f 6e 65 0a 20 20 20 69 6e 20 53 6f 75 |nd one. in Sou|
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000031f0 75 73 69 6e 67 20 70 72 65 2d 74 72 61 70 70 69 |using pre-trappi|
00003200 6e 67 20 28 75 73 75 61 6c 6c 79 20 77 69 74 68 |ng (usually with|
00003210 20 69 6e 74 65 72 63 65 70 74 69 6f 6e 29 2e 20 | interception). |
00003220 54 68 65 0a 20 20 20 77 69 6e 64 6f 77 73 20 63 |The. windows c|
00003230 6f 75 6c 64 20 64 6f 20 77 69 74 68 20 74 68 65 |ould do with the|
00003240 20 4e 65 77 65 72 4c 6f 6f 6b 20 90 74 69 74 6c | NewerLook .titl|
00003250 65 6a 6f 69 6e 74 91 20 73 70 72 69 74 65 20 69 |ejoint. sprite i|
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00003270 0a 20 20 20 61 6c 6f 6e 67 20 77 69 74 68 20 74 |. along with t|
00003280 68 65 20 52 69 73 63 20 50 43 20 65 72 72 6f 72 |he Risc PC error|
00003290 20 73 79 73 74 65 6d 20 73 70 72 69 74 65 73 2e | system sprites.|
000032a0 20 4e 6f 74 65 20 74 68 61 74 20 74 68 69 73 20 | Note that this |
000032b0 69 73 20 61 6e 20 4f 4c 44 0a 20 20 20 56 45 52 |is an OLD. VER|
000032c0 53 49 4f 4e 20 6f 66 20 33 44 45 72 72 6f 72 57 |SION of 3DErrorW|
000032d0 69 6e 64 6f 77 2c 20 77 68 69 63 68 20 79 6f 75 |indow, which you|
000032e0 20 73 68 6f 75 6c 64 20 6e 6f 74 20 61 63 74 75 | should not actu|
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00003300 20 20 4e 65 77 65 72 4c 6f 6f 6b 20 66 6f 72 20 | NewerLook for |
00003310 74 68 65 20 66 75 6c 6c 65 73 74 2c 20 6e 65 77 |the fullest, new|
00003320 65 73 74 20 76 65 72 73 69 6f 6e 2e 20 54 68 69 |est version. Thi|
00003330 73 2c 20 68 6f 77 65 76 65 72 2c 20 69 73 20 61 |s, however, is a|
00003340 20 62 65 74 74 65 72 0a 20 20 20 65 78 61 6d 70 | better. examp|
00003350 6c 65 20 6f 66 20 68 6f 77 20 74 6f 20 75 73 65 |le of how to use|
00003360 20 57 69 6d 70 53 57 49 56 65 2c 20 61 73 20 69 | WimpSWIVe, as i|
00003370 74 20 69 73 20 6c 65 73 73 20 63 6f 6d 70 6c 69 |t is less compli|
00003380 63 61 74 65 64 20 74 68 61 6e 20 74 68 65 0a 20 |cated than the. |
00003390 20 20 6c 61 74 65 73 74 20 76 65 72 73 69 6f 6e | latest version|
000033a0 2e 0a 20 2d 20 45 69 67 65 6e 53 79 73 49 6e 66 |.. - EigenSysInf|
000033b0 6f 2e 20 54 68 69 73 20 69 73 20 61 20 70 72 65 |o. This is a pre|
000033c0 74 74 79 20 75 73 65 6c 65 73 73 20 6f 6e 65 20 |tty useless one |
000033d0 74 68 61 74 20 63 68 61 6e 67 65 73 20 57 69 6d |that changes Wim|
000033e0 70 5f 52 65 61 64 53 79 73 49 6e 66 6f 0a 20 20 |p_ReadSysInfo. |
000033f0 20 32 20 61 6c 77 61 79 73 20 74 6f 20 72 65 74 | 2 always to ret|
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00003430 32 20 28 74 68 65 0a 20 20 20 57 49 4d 50 20 72 |2 (the. WIMP r|
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00003450 32 59 45 69 67 3d 3d 4c 6f 67 32 58 45 69 67 2c |2YEig==Log2XEig,|
00003460 20 77 68 69 63 68 20 69 73 20 73 69 6c 6c 79 29 | which is silly)|
00003470 2e 20 49 74 20 61 6c 73 6f 20 67 6f 65 73 0a 20 |. It also goes. |
00003480 20 20 90 62 65 65 70 91 20 69 66 20 74 68 65 20 | .beep. if the |
00003490 57 69 6d 70 20 72 65 74 75 72 6e 65 64 20 61 20 |Wimp returned a |
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000034c0 32 32 20 61 6e 64 20 74 68 65 0a 20 20 20 6c 69 |22 and the. li|
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000034e0 72 74 69 63 75 6c 61 72 6c 79 20 67 72 65 61 74 |rticularly great|
000034f0 20 62 65 63 61 75 73 65 20 6d 6f 73 74 20 70 72 | because most pr|
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00003540 66 20 69 74 73 20 61 66 6f 72 65 6d 65 6e 74 69 |f its aforementi|
00003550 6f 6e 65 64 20 62 6f 62 62 69 6e 73 6e 65 73 73 |oned bobbinsness|
00003560 29 0a 20 20 20 62 75 74 20 69 74 20 73 68 6f 77 |). but it show|
00003570 73 20 79 6f 75 20 68 6f 77 20 74 6f 20 70 72 65 |s you how to pre|
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00003590 72 61 70 20 53 57 49 73 20 61 74 20 74 68 65 20 |rap SWIs at the |
000035a0 73 61 6d 65 20 74 69 6d 65 20 28 61 73 0a 20 20 |same time (as. |
000035b0 20 69 6e 20 66 6f 6f 74 6e 6f 74 65 20 31 29 2e | in footnote 1).|
000035c0 0a 0a 20 54 68 65 20 73 6f 75 72 63 65 20 66 6f |.. The source fo|
000035d0 72 20 74 68 65 73 65 20 70 72 6f 67 72 61 6d 73 |r these programs|
000035e0 2c 20 61 6c 6f 6e 67 20 77 69 74 68 20 74 68 65 |, along with the|
000035f0 20 66 75 6c 6c 20 73 6f 75 72 63 65 20 74 6f 20 | full source to |
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00003610 6d 65 20 72 65 73 6f 75 72 63 65 73 20 66 6f 72 |me resources for|
00003620 20 33 44 45 72 72 6f 72 57 69 6e 64 6f 77 20 61 | 3DErrorWindow a|
00003630 72 65 20 74 6f 20 62 65 20 66 6f 75 6e 64 20 69 |re to be found i|
00003640 6e 20 74 68 65 20 53 6f 75 72 63 65 73 20 64 69 |n the Sources di|
00003650 72 65 63 74 6f 72 79 2e 0a 48 6f 77 65 76 65 72 |rectory..However|
00003660 2c 20 74 68 65 73 65 20 70 72 6f 67 72 61 6d 73 |, these programs|
00003670 20 72 65 71 75 69 72 65 20 42 41 58 20 74 6f 20 | require BAX to |
00003680 62 65 20 6c 6f 61 64 65 64 20 66 6f 72 20 74 68 |be loaded for th|
00003690 65 6d 20 74 6f 20 63 6f 6d 70 69 6c 65 2e 20 42 |em to compile. B|
000036a0 41 58 20 69 73 0a 44 6f 67 67 79 53 6f 66 74 91 |AX is.DoggySoft.|
000036b0 73 20 42 61 73 69 63 20 41 73 73 65 6d 62 6c 65 |s Basic Assemble|
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000036d0 63 68 20 70 72 6f 76 69 64 65 73 20 61 6c 6c 20 |ch provides all |
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00003720 75 73 65 66 75 6c 20 70 73 65 75 64 6f 2d 69 6e |useful pseudo-in|
00003730 73 74 72 75 63 74 69 6f 6e 73 2e 0a 59 6f 75 20 |structions..You |
00003740 63 61 6e 20 67 65 74 20 42 41 58 20 66 72 6f 6d |can get BAX from|
00003750 20 67 6f 6f 64 20 50 44 20 6c 69 62 72 61 72 69 | good PD librari|
00003760 65 73 20 61 6e 64 20 41 72 63 61 64 65 2c 20 44 |es and Arcade, D|
00003770 69 67 69 74 61 6c 20 44 61 74 61 62 61 6e 6b 20 |igital Databank |
00003780 61 6e 64 0a 46 75 72 7a 65 66 69 65 6c 64 20 48 |and.Furzefield H|
00003790 71 20 42 42 53 73 2e 20 49 74 91 73 20 65 73 73 |q BBSs. It.s ess|
000037a0 65 6e 74 69 61 6c 20 66 6f 72 20 42 61 73 69 63 |ential for Basic|
000037b0 20 61 73 73 65 6d 62 6c 65 72 20 70 72 6f 67 72 | assembler progr|
000037c0 61 6d 6d 65 72 73 21 0a 0a 20 49 66 20 79 6f 75 |ammers!.. If you|
000037d0 20 75 73 65 20 74 68 69 73 20 6d 6f 64 75 6c 65 | use this module|
000037e0 20 69 6e 20 61 20 70 72 6f 67 72 61 6d 2c 20 62 | in a program, b|
000037f0 65 20 73 75 72 65 20 74 6f 20 52 4d 45 6e 73 75 |e sure to RMEnsu|
00003800 72 65 20 76 65 72 73 69 6f 6e 20 30 2e 30 34 20 |re version 0.04 |
00003810 6f 72 0a 6c 61 74 65 72 20 2d 20 76 65 72 73 69 |or.later - versi|
00003820 6f 6e 73 20 30 2e 30 31 20 61 6e 64 20 30 2e 30 |ons 0.01 and 0.0|
00003830 32 20 61 72 65 20 4e 65 77 65 72 4c 6f 6f 6b 20 |2 are NewerLook |
00003840 71 75 69 63 6b 20 72 65 6c 65 61 73 65 73 20 77 |quick releases w|
00003850 69 74 68 20 62 75 67 73 20 69 6e 0a 70 6f 73 74 |ith bugs in.post|
00003860 2d 74 72 61 70 70 69 6e 67 2c 20 61 6e 64 20 76 |-trapping, and v|
00003870 65 72 73 69 6f 6e 20 30 2e 30 33 20 64 6f 65 73 |ersion 0.03 does|
00003880 20 6e 6f 74 20 66 65 61 74 75 72 65 20 68 69 67 | not feature hig|
00003890 68 2d 70 72 69 6f 72 69 74 79 20 53 57 49 20 74 |h-priority SWI t|
000038a0 72 61 70 70 69 6e 67 2c 0a 61 73 20 77 65 6c 6c |rapping,.as well|
000038b0 20 61 73 20 73 6f 6d 65 74 69 6d 65 73 20 65 6e | as sometimes en|
000038c0 74 65 72 69 6e 67 20 70 72 65 2d 63 6f 64 65 20 |tering pre-code |
000038d0 77 69 74 68 20 69 6e 74 65 72 72 75 70 74 73 20 |with interrupts |
000038e0 65 6e 61 62 6c 65 64 2e 0a 0a 20 54 68 69 73 20 |enabled... This |
000038f0 6d 6f 64 75 6c 65 20 69 73 20 66 72 65 65 77 61 |module is freewa|
00003900 72 65 2e 20 46 72 65 65 20 66 72 65 65 20 74 6f |re. Free free to|
00003910 20 64 69 73 74 72 69 62 75 74 65 20 61 6e 64 20 | distribute and |
00003920 75 73 65 2e 20 54 6f 20 63 6f 6e 74 61 63 74 20 |use. To contact |
00003930 6d 65 20 2d 0a 66 6f 72 20 70 72 61 69 73 65 2c |me -.for praise,|
00003940 20 74 6f 20 73 75 67 67 65 73 74 20 6e 65 77 20 | to suggest new |
00003950 62 69 74 73 20 74 6f 20 61 64 64 2c 20 6f 72 20 |bits to add, or |
00003960 28 68 65 61 76 65 6e 20 66 6f 72 62 69 64 29 20 |(heaven forbid) |
00003970 74 6f 20 72 65 70 6f 72 74 20 61 20 62 75 67 2c |to report a bug,|
00003980 0a 70 6c 65 61 73 65 20 77 72 69 74 65 20 74 6f |.please write to|
00003990 3a 0a 0a 20 20 41 6e 64 72 65 77 20 43 6c 6f 76 |:.. Andrew Clov|
000039a0 65 72 2c 0a 20 20 20 37 20 42 6c 61 63 6b 68 6f |er,. 7 Blackho|
000039b0 72 73 65 20 43 72 65 73 63 65 6e 74 2c 0a 20 20 |rse Crescent,. |
000039c0 20 20 41 6d 65 72 73 68 61 6d 2c 0a 20 20 20 20 | Amersham,. |
000039d0 20 42 75 63 6b 73 2e 2c 0a 20 20 20 20 20 20 48 | Bucks.,. H|
000039e0 50 36 20 36 48 50 2e 0a 0a 20 4f 72 20 70 68 6f |P6 6HP... Or pho|
000039f0 6e 65 20 6d 65 20 6f 6e 20 30 31 34 39 34 2d 34 |ne me on 01494-4|
00003a00 33 31 39 31 36 2c 20 73 65 6e 64 20 61 20 66 61 |31916, send a fa|
00003a10 78 20 6f 6e 20 30 31 34 39 34 2d 36 37 35 38 37 |x on 01494-67587|
00003a20 38 2c 20 73 65 6e 64 20 73 6f 6d 65 20 65 6d 61 |8, send some ema|
00003a30 69 6c 20 74 6f 0a 61 6a 63 40 64 6f 67 67 79 73 |il to.ajc@doggys|
00003a40 66 74 2e 64 65 6d 6f 6e 2e 63 6f 2e 75 6b 20 6f |ft.demon.co.uk o|
00003a50 72 20 65 76 65 6e 20 74 65 6c 65 78 20 6f 6e 20 |r even telex on |
00003a60 38 33 36 37 35 20 42 72 69 74 20 47 2e 0a |83675 Brit G..|
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