powercap-info: update help and man page for powercap file read privileges

Files used to always be world-readable, but changes the linux kernel have
limited some file permissions to owner (root) only access.

2 files changed, 10 insertions, 6 deletions

diff --git a/utils/man/man1/powercap-info.1 b/utils/man/man1/powercap-info.1
index e867823..eb70c40 100644
--- a/utils/man/man1/powercap-info.1
+++ b/utils/man/man1/powercap-info.1
@@ -1,4 +1,4 @@
-.TH "POWERCAP-INFO" "1" "2021-03-14" "powercap" "powercap\-info"
+.TH "POWERCAP-INFO" "1" "2021-04-24" "powercap" "powercap\-info"
 .SH "NAME"
 .LP
 powercap\-info \- get information from the Linux power capping framework
@@ -17,7 +17,7 @@ The control type \fINAME\fP must not be empty or contain a '.' or '/'.
 Prints the help screen
 .TP
 \fB\-v,\fR \fB\-\-verbose\fR
-Print errors when files are not available
+Print errors when files cannot be read
 .TP
 \fB\-p,\fR \fB\-\-control\-type\fR=\fINAME\fP
 Deprecated, provide \fINAME\fP as the first positional argument instead.
@@ -117,8 +117,11 @@ Print the energy counter for zone 0.
 Print the power limit for zone 1, subzone 0, constraint 0.
 .SH "REMARKS"
 .LP
-Some fields are optional and will only be printed if they are available
-unless \-v/\-\-verbose is set.
+Some fields are optional and/or may require administrative (super\-user)
+privileges to read.
+.br
+Fields will only be printed if they are available and readable, unless
+\-v/\-\-verbose is set.
 .br
 If no subzone/constraint\-specific outputs are requested, all available
 zones and constraints will be shown.
diff --git a/utils/powercap-info.c b/utils/powercap-info.c
index b7d0bc4..8451c50 100644
--- a/utils/powercap-info.c
+++ b/utils/powercap-info.c
@@ -175,7 +175,7 @@ static void print_usage(void) {
   printf("The control type NAME must not be empty or contain a '.' or '/'.\n\n");
   printf("Options:\n");
   printf("  -h, --help                   Print this message and exit\n");
-  printf("  -v, --verbose                Print errors when files are not available\n");
+  printf("  -v, --verbose                Print errors when files cannot be read\n");
   printf("  -p, --control-type=NAME      Deprecated, provide NAME as the first\n");
   printf("                               positional argument instead\n");
   printf("  -z, --zone=ZONE(S)           The zone/subzone numbers in the control type's\n");
@@ -205,7 +205,8 @@ static void print_usage(void) {
   printf("  -T, --c-max-time-window      Print constraint maximum allowed time window\n");
   printf("  -t, --c-min-time-window      Print constraint minimum allowed time window\n");
   printf("  -y, --c-name                 Print constraint name\n");
-  printf("\nSome fields are optional and will only be printed if they are available unless -v/--verbose is set.\n");
+  printf("\nSome fields are optional and/or may require administrative (super-user) privileges to read.\n");
+  printf("Fields will only be printed if they are available and readable, unless -v/--verbose is set.\n");
   printf("If no zone/constraint-specific outputs are requested, all available zones and constraints will be shown.\n");
   printf("\nEnergy units: microjoules (uJ)\n");
   printf("Power units: microwatts (uW)\n");