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.mp3-rwxr-xr-x 1 bball users 4341612 Jan 25 00:48Rippingtons-Carnival!.mp3 17 526-2 CH13 8/26/99 10:49 AM Page 297Internet Downloading and Browsing 297-rwxr-xr-x 1 bball users 5704848 Jan 25 01:15Rippingtons-Highroller.mp3-rwxr-xr-x 1 bball users 5480811 Jan 25 00:14Rippingtons-Indian Summer.mp3-rwxr-xr-x 1 bball users 5538079 Jan 25 01:02Rippingtons-Moka Java.mp3-rwxr-xr-x 1 bball users 5704686 Jan 25 09:55Rippingtons-St.Tropez.mp3-rwxr-xr-x 1 bball users 4606027 Jan 25 00:01Rippingtons-Vienna.mp3-rwxr-xr-x 1 bball users 5150057 Jan 25 00:48Rippingtons-Weekend in Monaco.mp3226 Transfer complete.ftp> bye221 Goodbye.#In this example, after logging in with my system username and password, I ended up inmy home directory instead of the default ftp directory.I then listed the contents of afolder on another mounted file system (you can t tell from the pathname or the files).Ifyou have an open PPP connection with your ISP and other users know your computer sIP address, you and other users can access your system s files and upload and downloadfiles.Downloading with the ncFTP ProgramThe ncftp command, found under the /usr/bin directory, is much like the original ftpcommand but features some unique improvements, such as the following:A visual mode with colorsA status bar with a separate command line and scrolling windowVisual status of downloading a progress meter to show elapsed and remainingtime for file downloadsBookmarks and a bookmark editor, so you can use abbreviated hostnames of com-puters13Like the ftp command, ncftp also has built-in help.The ncftp command, by MikeGleason of NCEMRSoft, also sports a number of interesting command-line options.Ifyou know the hostname of the computer and the complete path to a desired file, you canretrieve the file with a single command line, for example:# ncftp -a ftp://ftp.metalab.unc.edu/pub/Linux/apps/appliance/netlitng.tgz# nctp -a ftp.metalab.unc.edu/pub/Linux/apps/appliance/netlitng.tgz 17 526-2 CH13 8/26/99 10:49 AM Page 298298 Hour 13Both command lines connect to the ftp.metalab.unc.edu host, log in anonymously, andthen retrieve the file.This is a handy way to retrieve known files from remote computers.These command lines can also be used in shell scripts or combined with pipes to othercommands to process the incoming files.You can, for example, automatically translateincoming graphics files and save them in a specified directory:# ncftp -c rsd.gsfc.nasa.gov/pub/Weather/GOES-8/gif/mapped/color/conus/latest.gif | giftopnm | ppmtopcx >/home/ftp/weather.pcxThis example downloads a.GIF format weather satellite image, translates the graphicinto.pnm format and then.pcx format, and saves it in your system s ftp area.You canuse this approach to download and update files automatically, especially when used in acrontab file.(For details about using crontab, see Hour 24, Using Scheduling toAutomate System Management, or Hour 18, Personal Productivity Tools ).The ncftp status bar is helpful when interactively downloading files.Although I can tshow you the animation of the progress meter, when you use ncftp to download files,you get information on how the downloading is going, for example:wustl> get app-defaults.colorReceiving file: app-defaults.color100% 0 ==================================> 6583 bytes.ETA: 0:00app-defaults.color: 6583 bytes received in 5.77 seconds, 1.11 kB/s.ftp.wustl.edu /packages/NCSA/Web/Mosaic/Unix/binaries/app-defaultswustl>This shows a completed download of the X11 application defaults file for the MosaicWeb browser.If you do a lot of downloading via FTP using anonymous log in, create a filenamed.netrc in your home directory.Enter a single line like this:default login anonymous password yourusername@yourISP.comUse your email address for yourusername@yourISP.com.The next time youuse the ftp or ncftp command, you re automatically logged in!Browsing the World Wide Web with LinuxBrowsersThis section introduces you to several Web browsers for Linux.You can find thesebrowsers on your OpenLinux CD-ROM included with this book. 17 526-2 CH13 8/26/99 10:49 AM Page 299Internet Downloading and Browsing 299You can find other browsers, such as Chimera, Mosaic, and qweb athttp://metalab.unc.edu/pub/Linux/apps/www/browsers.This book doesn t have enough room to cover these browsers in detail.If you re inter-ested in learning about Web browsers or writing your own Web pages, I suggest you lookat the following books:HTML by Example, by Todd Staufer; QueUsing HTML, by Mark Brown, John Jung, and Tom Savola; QueFast Browsing with the lynx CommandThe Lynx browser, originally sponsored by the University of Kansas, does not supportgraphics, sound, or any of the other plug-in features of today s modern Web browsers.You can really like Lynx anyway because it s fast, efficient, and does not take up a lot ofdisk space.Lynx was designed to run on regular displays, or terminals, so you don t need to run theX Window System in order to use it [ Pobierz całość w formacie PDF ]