Download

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Revision as of 21:39, 29 October 2011 by Tonyforster (talk | contribs) (Verifying)
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To download is to copy a file from a web server to your local computer. Reliable downloading takes skill in the face of occasional technical challenges.

Back on the page that referred you here, you should have a download link that you are interested in. The following instructions relate to that page. Place the pages side by side.

How to Download

Using Firefox

  • right-click on the link, and a menu will appear,
  • click on Save Link As..., and a dialog window will appear asking you where to put the file,
  • tell it where you want the file put, and then a Downloads window will appear,
  • wait for the download to complete,
  • close the Downloads window,

The file will be in your Downloads directory.

Using Firefox on Mac OS X

Some Mac OS X systems lack a right-click button. Use control-click instead of right-click, then follow the generic Firefox instructions above.

Using Safari

  • control-click on the link, select Download Linked File As ..., and a Save As dialog will appear,
  • click on Save, the dialog will go away,
  • a Downloads window will appear,
  • wait for the download to complete,
  • close the Downloads window.

The file will be in your Downloads directory.

Using Internet Explorer

  • right-click on the link, select Download.

(to be completed by someone who knows how it works)

Using curl

curl is a download program that is very simple, very reliable, and can restart a partial download.

curl is available on Mac OS X by default, and can be installed on Linux or Microsoft Windows.

  • right-click on the link in your web browser, and select Copy Link Location (Firefox), or control-click on the link and select Copy Link (Safari),
  • start a Terminal, and then type
cd Downloads
  • then type
curl -OC -
  • press the space bar once more, to add a gap after the dash,
  • paste the link, so that the command looks like this:
curl -OC - http://something/
  • press enter, and the download will begin,
  • wait for the download to complete,
  • close the terminal.

To interrupt a download and resume it later, press Control/C. When you wish to resume, press up arrow once to recall the command, and then press enter to start it again. The download will resume from where you interrupted it.

Using wget

Start a Terminal, then type

wget --continue ${URL}

Where ${URL} is the link.

Using an XO

OS images can be downloaded using Sugar on the XO

The OS images are large, around 700MB and you must have enough free space for the download. The XO-1 has insufficient storage but the XO-1.5 and XO-1.75 can be used for downloading provided they do not have too many user files on them.

Browse can be used to download in Sugar or wget in Terminal can be used as described previously. With wget, you may first change the working directory to an attached USB device, such as,

cd /media/USB_DISK

and the file will be saved there with its proper file name.

Using an Internet browser, such as Browse, just click on a download link to initiate download. When the download has completed you can copy the file to a USB device by dragging the Journal entry. Sugar seems to crash at the end of the copy but the copy has been OK for me. Its worth checking the file size before using the USB copy for reflashing a laptop.

The file on the USB device has .bin appended to the file name. Either use Gnome or Terminal to rename the file before using the USB device to reflash a laptop.

Example, renaming filename.zd4 in Terminal:

cd /media
cd 'USB DISK'
mv filename.zd4.bin filename.zd4

Verifying

For some downloads, the directory also contains an md5 file that can be used to check that your copy of the file is intact. If you have downloaded both filename and filename.md5, execute this command in the directory to which they were downloaded to check the integrity of filename.

md5sum -c filename.md5

Problems

Displayed instead of Downloaded

If you use the normal click, some web servers cause your web browser to display the file instead of download it.

You must bypass this using one of the methods above.

Takes Too Long

A download that takes too long is usually caused by:

  • your internet service is too slow,
  • your internet service is being shared with other people,
  • the file is far too large.

You should either keep waiting, or use one of the interrupt and resume methods above.

Interrupted

A faulty or irregular internet service may cause a download to be interrupted.

You should either try the download again, or try to resume it using one of the methods above, such as wget or curl.

Downloaded File is a Document

We use several unusual file types that are not known by your computer. This may cause your computer to use an icon for the file that represents a document. We can't fix this. This can be ignored. Proceed to use the file as instructed.

In Mac OS X for example, a .zd file is shown in Finder as a document. An .img file does not, since .img is a file type that is used for disk images.

Other operating systems may indicate that the file is a document.