Need to install software from a floppy to a Mac that lacks a floppy drive? Tired of inserting a CD to play a game or consult an encyclopedia? You can solve these problems with disk-image files. For example, when Stephen Taylor of Castro Valley, California, got a new G4 at work, he wanted to install QuarkXPress on it. His version of the software came on CD but required an installation floppy; of course, the G4 has no floppy drive. No problem: he inserted the installation floppy into an older Mac and made a disk image using the Disk Copy utility that comes with the Mac OS. (The latest version of Disk Copy is available from Apple’s Software Library,
http://asu.info.apple.com.) He then copied the disk-image file to the G4 via the local network. After mounting the disk-image file as a disk on the G4again using Disk Copyhe was able to proceed with the installation.
If your new Mac isn’t on a local network, you can make the disk-image file on an older Mac that has Internet access, then either e-mail the file to the new Mac or transfer the file via one of the free storage sites on the Web, such as
Daniel Vanwie of Whittier, California, uses the $30 ShrinkWrap utility from Aladdin Systems (
) to create compressed, unencrypted, self-mounting disk-image files (with the extension .smi) from CD-ROMs. He recommends placing the resulting image file in the same folder as the application that requires it.
To make the CD image really easy to use, just record a simple AppleScript program that mounts the CD image as a disk and launches the application with one double-click. Start by opening Script Editor, a utility that comes with the Mac OS, and clicking the Record button in a new script window. Switch to the Finder, open the CD image, and then open the application. Switch back to Script Editor and click the Stop button. The following is an example of a recorded script that mounts a SimCity 3000 CD image (SimCity3000.smi) and then opens the SimCity application (SC3 1):
tell application "Finder"
select file "SimCity3000.smi" of folder
"SimCity 3000" of folder "Applications" of
select file "SC3 1" of folder "SimCity
3000" of folder "Applications" of startup disk
To turn the script into a program, choose Save As from the File menu; in the Save dialog box, set the Kind option to Application and turn on Never Show Startup Screen. To mount the CD image and start SimCity, double-click the icon that Script Editor creates.
Inbound from the Internet
I use the gateway software IPNetRouter from Sustainable Softworks (
) to share an Internet connection among the computers on my local network. The gateway also creates a firewall that prevents computers on the Internet from accessing computers on my local network. Is there a way to forward incoming packets to one computer on my local network so that it could, for example, serve Web pages?
Many Internet-sharing gateways can be con-figured to permit computers on the Internet to access a computer on your local network for a specific purpose, such as serving Web pages.
The sidebar “Inbound Port Mapping” illustrates the setup for IPNetRouter and another popular software gateway, Vicomsoft SoftRouter Plus (
Set Modem Speaker Volume
How can I edit a modem script to control the modem speaker volume? I’d like to have several uniquely named scripts that set the volume to off, maximum, and maybe a default level.
Kitchener-Waterloo, Ontario, Canada
You can edit modem scripts with any word processor or text editor, including SimpleText. A modem-script file contains plain text, though its type code is mlts, not TEXT. First make a copy of the script you want to modify. Then use a word processor or text editor that can open any type of file, such as the $119 BBEdit or free BBEdit Lite from Bare Bones Software (
). Or you can use a utility such as Daniel Azuma’s $10 shareware FileTyper (
) to change the file type code to TEXT (all caps), and then open the copy with any word processor or text editor.
Edit Modem Scripts
You can edit a modem script with a text editor such as SimpleText. The modem-initialization string comes several lines below
(A) and begins with the word
, not an exclamation point (B). Here, the command
(C) sets the modem speaker volume to its maximum level.
Scroll through the script until you find the line
@LABEL 3. Several lines below this, look for a line that begins
write “AT, followed by a bunch of letters, numbers, and symbols. This is the modem-initialization string of commands (see “Edit Modem Scripts”). This string can go to the modem piecemeal, in which case the commands appear on several lines (making them easier to decipher). Lines that begin with an exclamation point, however, are not part of the initialization string. They are treated as comments, not as commands.
You don’t need to know what all of the commands mean, but you can look them up in your modem’s documentation.
To set the modem volume to maximum, insert the command
at the end of the initialization string. To set the volume to medium, insert
L2; for low volume, insert
L1; and for lowest volume, insert
L0. You could insert another modem command to control the speaker:
to turn it off,
to turn it on. However, it’s easier to simply set the Sound option in the Modem control panel to On or Off. Another part of the modem script inspects this setting and issues an
When you finish editing the initialization string, save and close the file. If you had to change the file’s type code to TEXT to work with it, change it back to mlts (all lowercase) so the Modem control panel will recognize the file as a modem script.
LON POOLE answers readers’ questions and selects reader-submitted tips for this monthly column. He is a coauthor, with Todd Stauffer, of
Macworld Mac OS 9 Bible
(IDG Books Worldwide, 2000).
All shareware and freeware mentioned in
is available from the Macworld Online software library (
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Inbound Port Mapping
You can configure the Internet-sharing gateways IPNetRouter and Vicomsoft SoftRouter Plus to route specific types of incoming traffic to particular computers on a local network. Here, one computer (IP address 192.168.0.3) is set to get incoming FTP traffic (ports 20 and 21) and Timbuktu traffic (ports 407 and 1417 to 1420); another (IP address 192.168.0.2) is being set up to get Web server traffic (port 80).
Choose Port Mapping from the Window menu. In the Configure Entry section of the Port Mapping window, leave the first pop-up menu set to Any
and leave the first IP address box
alone (it should contain the public IP address your ISP assigned). Use the second pop-up menu
to set the TCP (or other protocol) port for the service, or type the port number directly
(D). For example, for a Web server, choose http from the menu or enter 80 in the text box. If the service uses a range of port numbers, such as 20 and 21 for FTP, type the first and last port numbers, separated by a hyphen. Next, select the second IP address box
and type the IP address of the local computer that will provide the service. Make sure its port number is correct
(F); generally it should be the same as the port number to the right of the public IP address
(D). You can ignore the entry box for Age
(G), but leave the Perm. option
turned on to retain this mapping when you quit IPNet-Router. Don’t turn on the Static option
unless your ISP has assigned you a static IP address. (You probably don’t have a static IP address unless you connect via cable modem or DSL.) Click Add to add the port mapping to the table at the top of the window. When you’ve finished mapping ports, close the Port Mapping window.
Configuring Vicomsoft SoftRouter Plus
Choose Inbound Mapping from the Network menu. Click New Host
and type the IP address of the local computer that will provide the Internet service. Use the pop-up menus
to specify a range of TCP port numbers for the service, or enter the numbers directly
(L). Click OK to finish.