nsIIOService provides a set of network utility functions.  This interface
 duplicates many of the nsIProtocolHandler methods in a protocol handler
 independent way (e.g., NewURI inspects the scheme in order to delegate
 creation of the new URI to the appropriate protocol handler).  nsIIOService
 also provides a set of URL parsing utility functions.  These are provided
 as a convenience to the programmer and in some cases to improve performance
 by eliminating intermediate data structures and interfaces.

 @status FROZEN
[scriptable, uuid(bddeda3f-9020-4d12-8c70-984ee9f7935e)]
interface nsIIOService : nsISupports

Attributes

 Returns true if networking is in "offline" mode. When in offline mode, 
 attempts to access the network will fail (although this is not 
 necessarily corrolated with whether there is actually a network 
 available -- that's hard to detect without causing the dialer to 
 come up).

 Changing this fires observer notifications ... see below.
attribute boolean offline

Methods

 Checks if a port number is banned. This involves consulting a list of
 unsafe ports, corresponding to network services that may be easily
 exploitable. If the given port is considered unsafe, then the protocol
 handler (corresponding to aScheme) will be asked whether it wishes to
 override the IO service's decision to block the port. This gives the
 protocol handler ultimate control over its own security policy while
 ensuring reasonable, default protection.

 @see nsIProtocolHandler::allowPort
boolean allowPort(in long aPort, in string aScheme) 
 Utility to extract the scheme from a URL string, consistently and
 according to spec (see RFC 2396).

 NOTE: Most URL parsing is done via nsIURI, and in fact the scheme
 can also be extracted from a URL string via nsIURI.  This method
 is provided purely as an optimization.

 @param aSpec the URL string to parse
 @return URL scheme

 @throws NS_ERROR_MALFORMED_URI if URL string is not of the right form.
ACString extractScheme(in AUTF8String urlString) 
 Returns the protocol flags for a given scheme.

 @param aScheme the URI scheme
 @return value of corresponding nsIProtocolHandler::protocolFlags
unsigned long getProtocolFlags(in string aScheme) 
 Returns a protocol handler for a given URI scheme.

 @param aScheme the URI scheme
 @return reference to corresponding nsIProtocolHandler
nsIProtocolHandler getProtocolHandler(in string aScheme) 
 Equivalent to newChannelFromURI(newURI(...))
nsIChannel newChannel(in AUTF8String aSpec, in string aOriginCharset, in nsIURI aBaseURI) 
 Creates a channel for a given URI.

 @param aURI nsIURI from which to make a channel
 @return reference to the new nsIChannel object
nsIChannel newChannelFromURI(in nsIURI aURI) 
 This method constructs a new URI from a nsIFile.

 @param aFile specifies the file path
 @return reference to a new nsIURI object
nsIURI newFileURI(in nsIFile aFile) 
 This method constructs a new URI by determining the scheme of the
 URI spec, and then delegating the construction of the URI to the
 protocol handler for that scheme. QueryInterface can be used on
 the resulting URI object to obtain a more specific type of URI.

 @see nsIProtocolHandler::newURI
nsIURI newURI(in AUTF8String aSpec, in string aOriginCharset, in nsIURI aBaseURI)