its name, release and version.
It also knows what hardware it runs on.
So, four of the fields of the struct are meaningful.
-On the other hand, the field \fInodename\fP is meaningless:
+On the other hand, the field
+.I nodename
+is meaningless:
it gives the name of the present machine in some undefined
network, but typically machines are in more than one network
and have several names.
Moreover, the kernel has no way of knowing
about such things, so it has to be told what to answer here.
-The same holds for the additional \fIdomainname\fP field.
+The same holds for the additional
+.I domainname
+field.
.LP
To this end Linux uses the system calls
.BR sethostname (2)
.BR setdomainname (2).
Note that there is no standard that says that the hostname set by
.BR sethostname (2)
-is the same string as the \fInodename\fP field of the struct returned by
+is the same string as the
+.I nodename
+field of the struct returned by
.BR uname ()
(indeed, some systems allow a 256-byte hostname and an 8-byte nodename),
but this is true on Linux.
The same holds for
.BR setdomainname (2)
-and the \fIdomainname\fP field.
+and the
+.I domainname
+field.
.LP
The length of the fields in the struct varies.
Some operating systems
the second
.\" That was also back before Linux 1.0
used 65;
-the third also uses 65 but adds the \fIdomainname\fP field.
+the third also uses 65 but adds the
+.I domainname
+field.
The glibc
.BR uname ()
wrapper function hides these details from applications,