tload: Report on lack of /proc/loadavg

Now that the library correctly returns an error if loadavg
is not available, tload can tell the user the bad news.

References:
 procps-ng/procps#227
 commit 8fcd14de18b998647ba47f5b35feb1d85e2d2f08

Signed-off-by: Craig Small <csmall@dropbear.xyz>

diff --git a/tload.c b/tload.c
index 279b4b53e49a73ba07a9cc179f02a5ac745bce49..993c13bc55671ae835b0396a2c5954cb6f4411a5 100644 (file)
--- a/tload.c
+++ b/tload.c
@@ -170,11 +170,20 @@ int main(int argc, char **argv)
        alrm(0);
 
        while (1) {
+        int rc;
 
                if (scale_fact < max_scale)
                        scale_fact *= 2.0;      /* help it drift back up. */
 
-               procps_loadavg(&av[0], &av[1], &av[2]);
+               if ((rc = procps_loadavg(&av[0], &av[1], &av[2])) < 0)
+        {
+            if (rc == -ENOENT)
+                xerrx(EXIT_FAILURE,
+                      _("Load average file /proc/loadavg does not exist"));
+            else
+                xerrx(EXIT_FAILURE,
+                      _("Unable to get load average"));
+        }
 
                do {
                        lines = av[0] * scale_fact;