Use errorMsg rather than fprintf.
diff --git a/procps/ps.c b/procps/ps.c
index a8d0005..6821359 100644
--- a/procps/ps.c
+++ b/procps/ps.c
@@ -97,20 +97,20 @@
 	if (tmp)
 		sscanf(tmp, "Pid:\t%d\n" "PPid:\t%d\n", &P->pid, &P->ppid);
 	else
-		fprintf(stderr, "Internal error!\n");
+		errorMsg("Internal error!\n");
 
 	/* For busybox, ignoring effective, saved, etc */
 	tmp = strstr(S, "Uid:");
 	if (tmp)
 		sscanf(tmp, "Uid:\t%d", &P->ruid);
 	else
-		fprintf(stderr, "Internal error!\n");
+		errorMsg("Internal error!\n");
 
 	tmp = strstr(S, "Gid:");
 	if (tmp)
 		sscanf(tmp, "Gid:\t%d", &P->rgid);
 	else
-		fprintf(stderr, "Internal error!\n");
+		errorMsg("Internal error!\n");
 
 }