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This section contains assorted operating-system facilities that don’t fit into other categories.
microcode-id/operating-system is bound to a symbol that specifies
the type of operating system that Scheme is running under. There are
two possible values: unix or nt.
The deprecated variable microcode-id/operating-system-name is
a string that’s equivalent to microcode-id/operating-system.
This variable is a string that identifies the particular variant of the operating system that Scheme is running under. Here are some of the possible values:
"GNU/Linux" "MacOSX" "Microsoft Windows NT 4.0 (Build 1381; Service Pack 3)"
For Windows systems, it is recommended that you match on the prefix of
this string and ignore the "Build" suffix. This is because the
suffix may contain information about service packs or fixes, while the
prefix will be constant for a particular version of Windows.
The next few procedures provide access to the domain name service
(DNS), which maintains associations between internet host
names such as "www.swiss.ai.mit.edu" and IP addresses,
such as 18.23.0.16. In MIT/GNU Scheme, we represent an internet host
name as a string, and an IP address as a byte vector of length
4 (byte vectors are just character strings that are accessed using
vector-8b-ref rather than string-ref). The bytes in an
IP address read in the same order as they do when written out:
(get-host-by-name "www.swiss") ⇒ #("\022\027\000\020")
Looks up the internet host name host-name using the DNS,
returning a vector of IP addresses for the corresponding host,
or #f if there is no such host. Usually the returned vector has
only one element, but if a host has more than one network interface, the
vector might have more than one element.
(get-host-by-name "www.swiss") ⇒ #("\022\027\000\020")
Does a reverse DNS lookup on ip-address, returning the
internet host name corresponding to that address, or #f if there
is no such host.
(get-host-by-address "\022\027\000\020") ⇒ "swissnet.ai.mit.edu"
Finds the “canonical” internet host name for host-name. For example:
(canonical-host-name "zurich") ⇒ "zurich.ai.mit.edu" (canonical-host-name "www.swiss") ⇒ "swissnet.ai.mit.edu"
In both examples, the default internet domain ‘ai.mit.edu’ is added
to host-name. In the second example, "www.swiss" is an
alias for another computer named "swissnet".
Returns the string that identifies the computer that MIT/GNU Scheme is running on. Usually this is an unqualified internet host name, i.e. the host name without the domain suffix:
(get-host-name) ⇒ "aarau"
Returns the canonical internet host name of the computer that MIT/GNU Scheme
is running on. So, in contrast to the example for get-host-name:
(os/hostname) ⇒ "aarau.ai.mit.edu"
Allocates and returns an IP address object. This is just a
string of a fixed length (current 4 bytes) into which an IP
address may be stored. This procedure is used to generate an
appropriate argument to be passed to
tcp-server-connection-accept.
(allocate-host-address) ⇒ "Xe\034\241"
Return an IP address object that specifies “any host”. This
object is useful only when passed as the address argument to
open-tcp-server-socket.
(host-address-any) ⇒ "\000\000\000\000"
Return an IP address object that specifies the local
loopback network interface. The loopback interface is a software
network interface that can be used only for communicating between
processes on the same computer. This address object is useful only when
passed as the address argument to open-tcp-server-socket.
(host-address-loopback) ⇒ "\177\000\000\001"
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