diff --git a/slsDetectorServers/slsDetectorServer/src/slsDetectorServer.c b/slsDetectorServers/slsDetectorServer/src/slsDetectorServer.c
index cbdbe12e2..c6e1da4b0 100644
--- a/slsDetectorServers/slsDetectorServer/src/slsDetectorServer.c
+++ b/slsDetectorServers/slsDetectorServer/src/slsDetectorServer.c
@@ -66,7 +66,7 @@ int main(int argc, char *argv[]) {
 #endif
 
     // help message
-    int helpMessageSize = 1200;
+    const size_t helpMessageSize = 1200;
     char helpMessage[helpMessageSize];
     {
         memset(helpMessage, 0, helpMessageSize);