zgenhostid.8: revisit

Reviewed-by: Richard Laager <rlaager@wiktel.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes #12212

man/man8/zgenhostid.8

@@ -18,72 +18,78 @@
 .\"
 .\" CDDL HEADER END
 .\"
-.\"
 .\" Copyright (c) 2017 by Lawrence Livermore National Security, LLC.
 .\"
 .Dd May 26, 2021
-.Dt ZGENHOSTID 8 SMM
+.Dt ZGENHOSTID 8
 .Os
+.
 .Sh NAME
 .Nm zgenhostid
-.Nd generate and store a hostid in
-.Em /etc/hostid
+.Nd generate host ID into /etc/hostid
 .Sh SYNOPSIS
 .Nm
 .Op Fl f
 .Op Fl o Ar filename
 .Op Ar hostid
+.
 .Sh DESCRIPTION
 Creates
 .Pa /etc/hostid
-file and stores hostid in it.
-If the user provides
-.Op Ar hostid
-on the command line, validates and stores that value.
-Otherwise, randomly generates a value to store.
-.Bl -tag -width "hostid"
+file and stores the host ID in it.
+If
+.Ar hostid
+was provided, validate and store that value.
+Otherwise, randomly generate an ID.
+.
+.Sh OPTIONS
+.Bl -tag -width "-o filename"
 .It Fl h
 Display a summary of the command-line options.
 .It Fl f
-Force file overwrite.
+Allow output overwrite.
 .It Fl o Ar filename
 Write to
 .Pa filename
-instead of default
-.Pa /etc/hostid
+instead of the default
+.Pa /etc/hostid .
 .It Ar hostid
 Specifies the value to be placed in
 .Pa /etc/hostid .
 It should be a number with a value between 1 and 2^32-1.
-If it is 0, zgenhostid will generate a random hostid.
+If
+.Sy 0 ,
+generate a random ID.
 This value
-.Sy must
+.Em must
 be unique among your systems.
 It
-.Sy must
-be expressed in hexadecimal and be exactly
-.Em 8
-digits long, optionally prefixed by
-.Em 0x .
+.Em must
+be an 8-digit-long hexadecimal number, optionally prefixed by
+.Qq 0x .
 .El
+.
 .Sh FILES
 .Pa /etc/hostid
+.
 .Sh EXAMPLES
 .Bl -tag -width Bd
 .It Generate a random hostid and store it
-.Dl # zgenhostid
+.Dl # Nm
 .It Record the libc-generated hostid in Pa /etc/hostid
-.Dl # zgenhostid "$(hostid)"
-.It Record a custom hostid (0xdeadbeef) in Pa /etc/hostid
-.Dl # zgenhostid deadbeef
-.It Record a custom hostid (0x01234567) in Pa /tmp/hostid No and ovewrite the file if it exists
-.Dl # zgenhostid -f -o /tmp/hostid 0x01234567
+.Dl # Nm Qq $ Ns Pq Nm hostid
+.It Record a custom hostid Po Ar 0xdeadbeef Pc in Pa /etc/hostid
+.Dl # Nm Ar deadbeef
+.It Record a custom hostid Po Ar 0x01234567 Pc in Pa /tmp/hostid No and ovewrite the file if it exists
+.Dl # Nm Fl f o Ar /tmp/hostid 0x01234567
 .El
+.
 .Sh SEE ALSO
 .Xr genhostid 1 ,
 .Xr hostid 1 ,
 .Xr sethostid 3 ,
 .Xr spl 4
+.
 .Sh HISTORY
 .Nm
 emulates the
@@ -91,4 +97,4 @@ emulates the
 utility and is provided for use on systems which
 do not include the utility or do not provide the
 .Xr sethostid 3
-call.
+function.