Linking to the web
When whole URLs (i.e. URLs with '://' embeded in their name) are used within a
<a>HREF=...</a> link in a (%ht) hypertext document, the default web
browser is invoked to process the link.
A ClearWin+ routine is also available to perform this task:
This routine uses the Windows shell to open the URL. As a result it can be
used to 'open' other objects such as a file with a name that has a registered
extension (e.g. .DOC files). You can use this routine in a ClearWin+ window
call-back function (attached to a menu item or button) in order to create a
link to a web site or document.
This facility is also available via the
INTERNET_HYPERLINK standard call-back function.
There is also a routine to read the contents of a URL (assuming the machine
has access to the internet):
If this routine succeeds (i.e. an internet connection is available and the URL
can be accessed), ERROR is set to zero and the data from the URL is transferred
to the specified file (which can be a full path name). If MODE=0, the data is
assumed to be text and new lines are converted to DOS style. If MODE=1, binary
data is assumed.
The URL can be quite general. In particular, you can use an FTP address
assuming anonymous access is possible, or an HTTP address with extra
information attached. For example, you could query a search engine directly
using this routine.
If necessary, the system will dial up the service provider to process this
call. By default the connection will not be closed after the transfer has
completed. The following call will close a modem connection if one exists.
The function DOWNLOAD@ is similar to
READ_URL@ but reads the download into memory.