Allow run_command to take a list instead of a string.

When it does this, commands are not executed via the shell, but are executed
directly. (See the documentation for 'exec' for an explanation of this).
Existing modules that pass a string are unaffected.

The rationale for this change is for the Pgrep (and similar) modules, where it
was picking up the 'sh -c pgrep' process and including it in the process
count. Executing pgrep directly prevents this.

git-svn-id: https://labs.omniti.com/resmon/branches/resmon2@309 8c0face9-b7db-6ec6-c4b3-d5f7145c7d55

lib/Resmon/ExtComm.pm

@@ -33,10 +33,10 @@ sub clean_up {
     }
 }
 
-sub run_command($) {
+sub run_command {
     # Run a command just like `cmd`, but store the pid and stdout handles so
     # they can be cleaned up later. For use with alarm().
-    my $cmd = shift;
+    my @cmd = @_;
     pipe(my ($r, $w));
     my $pid = fork();
     if($pid) {
@@ -50,7 +50,7 @@ sub run_command($) {
         eval {
             open(STDOUT, ">&", $w);
             close($r);
-            exec($cmd);
+            exec(@cmd);
         };
         exit();
     }

resources/testmod

@@ -46,12 +46,26 @@ our @EXPORT_OK = qw/cache_command run_command/;
 
 sub cache_command($$) {
     my $command = shift;
-    return `$command`;
+    run_command($command);
 }
 
-sub run_command($) {
-    my $command = shift;
-    return `$command`;
+sub run_command {
+    my @cmd = @_;
+    pipe(my ($r, $w));
+    my $pid = fork();
+    if($pid) {
+        close($w);
+        my @lines = <$r>;
+        waitpid($pid, 0);
+        return join("", @lines);
+    } else {
+        eval {
+            open(STDOUT, ">&", $w);
+            close($r);
+            exec(@cmd);
+        };
+        exit();
+    }
 }
 
 1;