diff --git a/src/globals.h b/src/globals.h
index 27a8d68..b8fd231 100644
--- a/src/globals.h
+++ b/src/globals.h
@@ -1171,9 +1171,14 @@
 EXTERN FILE	*scriptout  INIT(= NULL);   // stream to write script to
 EXTERN int	read_cmd_fd INIT(= 0);	    // fd to read commands from
 
-// volatile because it is used in signal handler catch_sigint().
-EXTERN volatile sig_atomic_t got_int INIT(= FALSE); // set to TRUE when interrupt
-						// signal occurred
+// Set to TRUE when an interrupt signal occurred.
+// Volatile because it is used in signal handler catch_sigint().
+EXTERN volatile sig_atomic_t got_int INIT(= FALSE);
+
+// Set to TRUE when SIGUSR1 signal was detected.
+// Volatile because it is used in signal handler catch_sigint().
+EXTERN volatile sig_atomic_t got_sigusr1 INIT(= FALSE);
+
 #ifdef USE_TERM_CONSOLE
 EXTERN int	term_console INIT(= FALSE); // set to TRUE when console used
 #endif