Add a -r option to print the running kernel version.

MFC after:	1 week

bin/freebsd-version/freebsd-version.1

@@ -25,15 +25,15 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd October 5, 2013
+.Dd November 14, 2017
 .Dt FREEBSD-VERSION 1
 .Os
 .Sh NAME
 .Nm freebsd-version
 .Nd print the version and patch level of the installed system
 .Sh SYNOPSIS
 .Nm
-.Op Fl ku
+.Op Fl kru
 .Sh DESCRIPTION
 The
 .Nm
@@ -50,21 +50,22 @@ if a new kernel has been installed but the system has not yet
 rebooted,
 .Nm
 will print the version and patch level of the new kernel.
+.It Fl r
+Print the version and patch level of the running kernel.
+Unlike
+.Xr uname 1 ,
+this is unaffected by environment variables.
 .It Fl u
 Print the version and patch level of the installed userland.
 These are hardcoded into
 .Nm
 during the build.
 .El
 .Pp
-If both
-.Fl k
-and
-.Fl u
-are specified,
+If several of the above options are specified,
 .Nm
-will print the kernel version first, then the userland version, on
-separate lines.
+will print the installed kernel version first, then the running kernel
+version, and finally the userland version, on separate lines.
 If neither is specified, it will print the userland version only.
 .Sh IMPLEMENTATION NOTES
 The

bin/freebsd-version/freebsd-version.sh.in

@@ -38,7 +38,7 @@ LOADER_RE1='^\([A-Z_a-z][0-9A-Z_a-z]*=[-./0-9A-Z_a-z]\{1,\}\).*$'
 LOADER_RE2='^\([A-Z_a-z][0-9A-Z_a-z]*="[-./0-9A-Z_a-z]\{1,\}"\).*$'
 KERNEL_RE='^@@TYPE@@ \([-.0-9A-Za-z]\{1,\}\) .*$'
 
-progname=$(basename $0)
+progname=${0##*/}
 
 #
 # Print an error message and exit.
@@ -70,6 +70,13 @@ kernel_version() {
 	what -qs "$kernfile" | sed -n "s/$KERNEL_RE/\\1/p"
 }
 
+#
+# Print the version of the currently running kernel.
+#
+running_version() {
+	sysctl -n kern.osrelease
+}
+
 #
 # Print the hardcoded userland version.
 #
@@ -81,7 +88,7 @@ userland_version() {
 # Print a usage string and exit.
 #
 usage() {
-	echo "usage: $progname [-ku]" >&2
+	echo "usage: $progname [-kru]" >&2
 	exit 1
 }
 
@@ -90,11 +97,14 @@ usage() {
 #
 main() {
 	# parse command-line arguments
-	while getopts "ku" option ; do
+	while getopts "kru" option ; do
 		case $option in
 		k)
 			opt_k=1
 			;;
+		r)
+			opt_r=1
+			;;
 		u)
 			opt_u=1
 			;;
@@ -108,15 +118,20 @@ main() {
 	fi
 
 	# default is -u
-	if [ $((opt_k + opt_u)) -eq 0 ] ; then
+	if [ $((opt_k + opt_r + opt_u)) -eq 0 ] ; then
 		opt_u=1
 	fi
 
-	# print kernel version
+	# print installed kernel version
 	if [ $opt_k ] ; then
 		kernel_version
 	fi
 
+	# print running kernel version
+	if [ $opt_r ] ; then
+		running_version
+	fi
+
 	# print userland version
 	if [ $opt_u ] ; then
 		userland_version