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.After you do this, you should edit the /etc/inittab file as described earlier, and use mgetty to listen to the serial port for example,3:2345:respawn:/sbin/mgetty -s 38400 ttyS1As mentioned before, any edits of the /etc/inittab file are potentiallyhazardous.Always have a spare boot disk and make a backup of the filefirst.CAUTION9 Using Communications Programs 159After you make this change, save the file and reboot the computer.Now, not only can youreceive faxes, but you also can dial in from an outside line and run Linux programs.To seeif any faxes have arrived, you ll have to explicitly look at the /var/spool/fax/incomingdirectory for example,# ls -A /var/spool/fax/incomingfn4878f9aS1-_IBM-APTIVA-M61-_.01 fn4878f9aS1-_IBM-APTIVA-M61-_.02This shows that a two-page fax awaits reading.You can read the faxes by first converting themto the portable bitmap file format for example,9# cat /var/spool/fax/incoming/*.01 | g32pbm > faxpage1.pbmAfter you convert these fax files to the portable bitmap format, you can then use the X11 xvclient or the ImageMagick display X11 program to read or print your faxes.As you can see, you ll have several choices of faxing documents with Linux.The sendfaxprogram, like the efax family of programs, also accepts other types of files to fax, and has manyother options.Read the documentation for this program to find out the details. 160 Hour 99 Connecting to the Internet 161PARTIIIHour 101 0Connecting to theInternetIn this hour, you ll learn how to set up your Linux system to connect to theInternet by using the serial line Point-to-Point Protocol, known as PPP.Afterfollowing the directions in this lesson, you should be able to connect to theInternet through your Internet service provider (ISP) to do email, Webbrowsing, or file transfers.This hour s lesson not only shows you how to do thisin the simplest, most basic way possible, but also points you to sources ofinformation for more details so that you can troubleshoot or fine-tune yourconnection.I m recommending that you use a PPP connection for several reasons:Although it s complex, it s easy to set up.You ll find documentation and details on the protocol.You can read the comp.protocols.ppp newsgroup for information.It offers security on both ends of the connection.It s a common protocol supported by nearly all ISPs.It s flexible enough to accommodate different types of connections. 162 Hour 10This hour starts by listing some of the hardware and software prerequisites for Linux, andthen asking you for some necessary information you ll need from your ISP.With thatinformation, you ll create a set of customized scripts you can use to start or stop yourconnection.You ll also learn about some handy utilities you can use to diagnose yourconnection, and some other programs you can use to monitor your sessions.Hardware You ll NeedYou probably already have all the hardware you need: a modem, a modem cable if yourmodem is external, and a phone line.But there are other considerations, such as your serialport or modem speed.One great thing about Linux is that it runs well, even on older computers.Although graphics-intensive applications such as X can tax the capabilities of older, slower PCs, you don t needX, a fancy display monitor, or a 16MB VRAM accelerated 3D video card to use PPP.Youwill, however, need a serial card to support First-In-First-Out serial buffering.If you can use your modem under Linux to dial out and connect by using the minicomprogram or C-Kermit, chances are you won t have any problems.If you re using a PC Cardmodem, and the cardmgr PCMCIA device manager recognizes and initializes your modem,you should be OK.One way to check is to use the dmesg program, which displays the file/var/log/dmesg created when you start Linux.Run the dmesg program (piped through theless command), and look for lines in the output similar to the following:# dmesg | less
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