Jun 94 Tips
Volume Number: 10
Issue Number: 6
Column Tag: Tips & Tidbits
Tips & Tidbits 
By Scott T Boyd, Editor
Note: Source code files accompanying article are located on MacTech CD-ROM orsource code disks.
Tip Of The Month
MPW Quoting Time Saver
Every self respecting Mac programmer knows that in MPW, string literals and
shell variables containing spaces must be quoted. What many experienced shell users
don’t know is that the option-space character, which looks just like a regular space,
bypasses this requirement when dealing with the file system. Amaze your friends by
typing Directory "{Boot}"Desktop Folder without any quotes (slip in that option-space
while they’re not looking). It’s a great time saver and party ice breaker!
Without an option-space:
Directory "{Boot}"desktop folder
### Directory - Too many parameters were specified.
# Usage - Directory [-q | directory]
With an option-space, no error is returned:
Directory "{Boot}"Desktop Folder
- Paul Mercer
mercer@netcom.com
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Slimming down “fat binaries” with MPW
Fat binaries contain both Macintosh 68K and PowerPC code, so they can run on
any Mac hardware and take advantage of whatever processor is present.
A fat binary contains 68K executable 'CODE' resources and other standard Mac
resources in the resource fork, and PowerPC Executable Format (PEF) code in the data
fork. It also includes a 'cfrg' resource, to tell a Power Mac to ignore CODE resources at
startup and look for PEF code in the data fork. A 68K Mac ignores the 'cfrg' resource
and PEF code, using the 'CODE' resources instead.
This is fine for developers who only want to ship only one version of their
product, and for users who want to be able to just click and go on any system, even
when file-sharing across a network mixed with 68K and Power Macs. But lone power
users with limited disk space may wish to perform liposuction on fat binaries, and
MPW makes it easy.
To convert a fat binary to a “68K only” application:
/* 1 */
# MPW Script "To68K
If {#} != 1
Echo "# Usage: {0} fat_ application_name
Else
Derez -skip cfrg "{1}" | Rez -o "{1}" # eliminate 'cfrg' resource
Duplicate -y -r "{1}" "{1}.temp" # eliminate data fork
Rename -y "{1}.temp" "{1}" # replace original file
End
To convert a fat binary into a “Power Mac only” application:
/* 2 */
# MPW Script "ToPowerMac
If {#} != 1
Echo "# Usage: {0} fat_ application_name
Else
Derez -skip CODE "{1}" | Rez -o "{1}" # eliminate 'CODE'
resources
End
Caveats: Neither of these scripts check if they are really operating on a fat
binary, nor do they know whether a native version might need one or more
CODEsegments, so be careful how you apply them, and please don’t perform surgery on
your only copy of any file!
- Lee David Rimar, Absoft Corporation
Ever heard of setkey?
I’m just amazed at some of the SmartFriends™ I know who haven’t heard of
SetKey, an MPW command that has been around for quite some time. It just goes to
show how few people read release notes or manuals for MPW. Maybe it’s just that
these people all worked at Apple, where coming by production versions of manuals can
be enough of a chore that it’s not worth the trouble.
At any rate, SetKey lets you attach a script to any key or key combination on your
keyboard, even the function keys on the extended keyboard. So tip #1 is to try out
SetKey. SetKey uses the following syntax:
/* 3 */
SetKey | -r | [modifierkey-] key[-modifierkey-]key] [string]
modifierkey = command | option | shift | control
-r # revert to the default key assignments
Tip #2 is to enter SetKey in a shell window, and see what’s already set. You
might be surprised at some of the things MPWalready knows how to do with key
combinations.
Function keys are F1-F15. Other keys are referenced by name, such as the
following:
/* 4 */
setkey Option-Command-Downarrow MoveEndOfFile
setkey Option-Command-Uparrow MoveStartOfFile
setkey Option-Shift-Delete Beep
setkey Option-Shift-Escape Beep
setkey Option-Shift-Clear 'Clear § "{active}"'
setkey Option-Shift-Del Beep
setkey Option-Shift-Leftarrow SelectWordLeft
For Tip #3 and following, here are some scripts Iuse a lot:
• To mark the current selection in the active window, Iuse function key F8.
/* 5 */
# mark current selection in the Active window
setkey F8 'Mark § "`Catenate "{Active}".§`" "{Active}" -y'
• Here’s a fun one. It sorts the current selection.
/* 6 */
# sort the current selection in the Active window
SetKey F12 'sort -o "{SysTempFolder}MPW.Scratch" ∂
"{Active}".§ ; ∂
catenate "{SysTempFolder}MPW.Scratch" > "{Active}".§ ; ∂
delete "{SysTempFolder}MPW.Scratch"'
• Finally, here are three simple scripts Iuse frequently. I add them to a new menu,
and Igive that menu the cloverleaf character from the command key as a title.
The first line sets a variable to have the value of the cloverleaf character. Where
you see the cloverleaf below, you’ll probably see a n character when you type
control-Q.
/* 7 */
Set Key Cmd # cloverleaf = ctl-Q
This one compiles the current selection, then dumps the object code that the C
compiler generated.
/* 8 */
AddMenu {Key} 'C->DumpObj §' 'C "{Active}.§" -mc68020 -mbg ∂
off -o "{SysTempFolder}temp.c.o"; ∂
DumpObj "{SysTempFolder}temp.c.o" -co'
This one assembles the current selection, then dumps the resulting object code.
/* 9 */
AddMenu {Key} 'Asm->DumpObj §' 'Asm "{Active}.§" ∂
-o "{SysTempFolder}temp.c.o"; ∂
DumpObj "{SysTempFolder}temp.c.o" -co'
This one compares the current selection in the active window to the
selection in the target window.
/* 10 */
AddMenu {Key} 'Compare {Active}.§ §' ∂
'Compare "{Active}.§" "{Target}.§" >> "{Worksheet}"'
- Gordon Sheridan, General Magic
Assembling kährs
When putting together a Kährs wood plank floor, go ahead and shell out the thirty
dollars or so for the “pull-up” tool. It’s not entirely obvious why you’d need it when
you first start putting the floor together, although it looks like it might be handy to
cinch up planks once you have the whole row down. It turns out not to help for that
(the friction is simply too great along the length of the plank), but it does wonders
when you start laying the last couple of rows. Up to that point, you can just use a
tap-block and a mallet to tighten the new plank against the previous row. Once you get
close to the far wall, though, there’s no room to swing the mallet, much less place the
tap-block. The pull-up tool fits into the groove which is right against the wall, and
gives you some room to swing the mallet, and pull the board into place.
- Al Borland, Chicago, IL
[Thanks for the tip, Al. It’s definitely better than putting a hole in the drywall
with a prybar. You might want to send this tip to HomeTech Magazine as well - I
understand they give away a free can of putty!. - Ed kag]