pmcstat.8: fix -a flag description; improve -m flag to match

The -a flag reads a file saved by -O, not -o.

The -m flag requires the -R flag.  Copy that paragraph from -a.

Reviewed by:	adrian
Approved by:	kib (mentor)
MFC after:	1 week
Sponsored by:	Dell Inc

2 files changed, 9 insertions, 3 deletions

diff --git a/usr.sbin/pmcstat/pmcstat.8 b/usr.sbin/pmcstat/pmcstat.8
index d34cb6b..9a204a4 100644
--- a/usr.sbin/pmcstat/pmcstat.8
+++ b/usr.sbin/pmcstat/pmcstat.8
@@ -25,7 +25,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd Oct 27, 2014
+.Dd March 27, 2015
 .Dt PMCSTAT 8
 .Os
 .Sh NAME
@@ -236,7 +236,7 @@ This option requires the
 .Fl R
 option to read in samples that were previously collected and
 saved with the
-.Fl o
+.Fl O
 option.
 .It Fl c Ar cpu-spec
 Set the cpus for subsequent system mode PMCs specified on the
@@ -301,6 +301,12 @@ is a
 this information is sent to the output file specified by the
 .Fl o
 option.
+This option requires the
+.Fl R
+option to read in samples that were previously collected and
+saved with the
+.Fl O
+option.
 .It Fl n Ar rate
 Set the default sampling rate for subsequent sampling mode
 PMCs specified on the command line.
diff --git a/usr.sbin/pmcstat/pmcstat.c b/usr.sbin/pmcstat/pmcstat.c
index a045706..77613b4 100644
--- a/usr.sbin/pmcstat/pmcstat.c
+++ b/usr.sbin/pmcstat/pmcstat.c
@@ -940,7 +940,7 @@ main(int argc, char **argv)
 		errx(EX_USAGE, "ERROR: options -T and -l are mutually "
 		    "exclusive.");
 
-	/* -m option is allowed with -R only. */
+	/* -a and -m require -R */
 	if (args.pa_flags & FLAG_DO_ANNOTATE && args.pa_inputpath == NULL)
 		errx(EX_USAGE, "ERROR: option %s requires an input file",
 		    args.pa_plugin == PMCSTAT_PL_ANNOTATE ? "-m" : "-a");