diskinfo(8): introduce new option -l

In modes -p or -s, add an option -l to start each line
with a device name separated with a tab. Update the manual page.
Add an example to list names with corresponding serial numbers:

diskinfo -ls /dev/da?

(cherry picked from commit e333110d1de748e50051d1305b5438d1bc54eeb4)

2 files changed, 32 insertions, 6 deletions

diff --git a/usr.sbin/diskinfo/diskinfo.8 b/usr.sbin/diskinfo/diskinfo.8
index 72fd1df4eb08..970bafd4f8e5 100644
--- a/usr.sbin/diskinfo/diskinfo.8
+++ b/usr.sbin/diskinfo/diskinfo.8
@@ -27,7 +27,7 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.Dd July 4, 2017
+.Dd March 5, 2024
 .Dt DISKINFO 8
 .Os
 .Sh NAME
@@ -38,10 +38,12 @@
 .Op Fl citSvw
 .Ar disk ...
 .Nm
-.Op Fl p
+.Op Fl l
+.Fl p
 .Ar disk ...
 .Nm
-.Op Fl s
+.Op Fl l
+.Fl s
 .Ar disk ...
 .Sh DESCRIPTION
 The
@@ -57,6 +59,13 @@ Print fields one per line with a descriptive comment.
 Perform a simple measurement of the I/O read command overhead.
 .It Fl i
 Perform a simple IOPS benchmark.
+.It Fl l
+In case of
+.Fl p
+or
+.Fl s
+modes prepend each line of an output with a device name using a tab
+character as a separator.
 .It Fl p
 Return the physical path of the disk.
 This is a string that identifies the physical path to the disk in the
@@ -80,6 +89,14 @@ with the following fields: device name, sectorsize, media size in bytes,
 media size in sectors, stripe size, stripe offset, firmware cylinders,
 firmware heads, and firmware sectors.
 The last three fields are only present if the information is available.
+.Sh EXAMPLES
+List first ten (at most)
+.Xr da 4
+devices with corresponding serial numbers:
+.Pp
+.Dl diskinfo -ls /dev/da?
+.Sh SEE ALSO
+.Xr da 4
 .Sh HISTORY
 The
 .Nm
diff --git a/usr.sbin/diskinfo/diskinfo.c b/usr.sbin/diskinfo/diskinfo.c
index 42227d793e99..0f62817ef1cb 100644
--- a/usr.sbin/diskinfo/diskinfo.c
+++ b/usr.sbin/diskinfo/diskinfo.c
@@ -58,11 +58,14 @@
 static void
 usage(void)
 {
-	fprintf(stderr, "usage: diskinfo [-cipsStvw] disk ...\n");
+	fprintf(stderr, "usage: diskinfo [-ciStvw] disk ...\n"
+			"       diskinfo [-l] -p disk ...\n"
+			"       diskinfo [-l] -s disk ...\n"
+				);
 	exit (1);
 }
 
-static int opt_c, opt_i, opt_p, opt_s, opt_S, opt_t, opt_v, opt_w;
+static int opt_c, opt_i, opt_l, opt_p, opt_s, opt_S, opt_t, opt_v, opt_w;
 
 static bool candelete(int fd);
 static void speeddisk(int fd, off_t mediasize, u_int sectorsize);
@@ -88,7 +91,7 @@ main(int argc, char **argv)
 	u_int	sectorsize, fwsectors, fwheads, zoned = 0, isreg;
 	uint32_t zone_mode;
 
-	while ((ch = getopt(argc, argv, "cipsStvw")) != -1) {
+	while ((ch = getopt(argc, argv, "cilpsStvw")) != -1) {
 		switch (ch) {
 		case 'c':
 			opt_c = 1;
@@ -98,6 +101,9 @@ main(int argc, char **argv)
 			opt_i = 1;
 			opt_v = 1;
 			break;
+		case 'l':
+			opt_l = 1;
+			break;
 		case 'p':
 			opt_p = 1;
 			break;
@@ -169,6 +175,9 @@ main(int argc, char **argv)
 				goto out;
 			}
 		} else {
+			if (opt_l && (opt_p || opt_s)) {
+				printf("%s\t", argv[i]);
+			}
 			if (opt_p) {
 				if (ioctl(fd, DIOCGPHYSPATH, physpath) == 0) {
 					printf("%s\n", physpath);