From ef3fbc29fc423e831c14e03f40b2f9c4b73b48e4 Mon Sep 17 00:00:00 2001
From: Nick Briggs <nicholas.h.briggs@gmail.com>
Date: Wed, 14 Jun 2017 17:53:13 -0700
Subject: [PATCH] Add extern declaration for "flushing", a flag to
 enable/disable calls to fflush(stdout) after each call to printf() in the
 debug/tracing code.  Too frequent calls slow things down.

	modified:   inc/dbprint.h
	modified:   src/main.c
---
 inc/dbprint.h | 14 +++++++++-----
 src/main.c    |  2 ++
 2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/inc/dbprint.h b/inc/dbprint.h
index 64df746..8240a4b 100755
--- a/inc/dbprint.h
+++ b/inc/dbprint.h
@@ -38,8 +38,12 @@
 
 	/* For debugging print statements */
 
+#if defined(DEBUG) || defined(TRACE) || defined(OPTRACE) || defined(FNTRACE) || defined(FNSTKCHECK)
+extern int flushing;
+#endif
+
 #ifdef DEBUG
-#define DBPRINT(X)   printf X; fflush(stdout)
+#define DBPRINT(X)   printf X ; if (flushing) fflush(stdout);
 #define DEBUGGER(X)  X;
 #else
 #define DBPRINT(X)
@@ -50,7 +54,7 @@
 	/* For trace print statements */
 
 #ifdef TRACE
-#define TPRINT(X)   printf X; fflush(stdout);
+#define TPRINT(X)   printf X; if (flushing) fflush(stdout);
 #define TRACER(X)  X;
 #else /* TRACE */
 
@@ -63,7 +67,7 @@
 	/* For tracing individual opcode executions */
 
 #ifdef OPTRACE
-#define OPTPRINT(X)   printf X; fflush(stdout);
+#define OPTPRINT(X)   printf X; if (flushing) fflush(stdout);
 #define OPTRACER(X)  X;
 #else
 #define OPTPRINT(X)
@@ -74,7 +78,7 @@
 	/* For tracing function calls */
 
 #ifdef FNTRACE
-#define FNTPRINT(X)   printf X; fflush(stdout);
+#define FNTPRINT(X)   printf X; if (flushing) fflush(stdout);
 #define FNTRACER(X)  X;
 #else
 #define FNTPRINT(X)
@@ -85,7 +89,7 @@
 	/* For function-call & return stack checking */
 
 #ifdef FNSTKCHECK
-#define FNCHKPRINT(X)   printf X; fflush(stdout);
+#define FNCHKPRINT(X)   printf X ; if (flushing) fflush(stdout);
 #define FNCHECKER(X)  X;
 #else
 #define FNCHKPRINT(X)
diff --git a/src/main.c b/src/main.c
index 94c05c3..2a5b1c4 100644
--- a/src/main.c
+++ b/src/main.c
@@ -273,6 +273,8 @@ int Lisp_Xinitialized = FALSE;
 char sysout_name[1024]; /* Set by read_Xoption, in the X version. */
 int sysout_size = 0;    /* ditto */
 
+int flushing = FALSE; /* see dbprint.h if set, all debug/trace printing will call fflush(stdout) after each printf */
+
 #if defined(DOS) || defined(XWINDOW)
 #include "devif.h"
 extern DspInterface currentdsp;