Define and support EX_NOLOG mode flag to sbbs_t::external(), if set,

intercepted output to stderr won't be logged.

src/sbbs3/sbbsdefs.h

@@ -814,6 +814,7 @@ enum {							/* readmail and delmailidx which types		*/
 #define EX_CHKTIME	XTRN_CHKTIME	/* Check time left						*/
 #define EX_NOECHO	XTRN_NOECHO		/* Don't echo stdin to stdout 			*/
 #define EX_STDIO	(EX_STDIN|EX_STDOUT)
+#define EX_NOLOG	(1<<30)		/* Don't log intercepted stdio				*/
 #define EX_CONIO	(1<<31)		/* Intercept Windows console I/O (doorway)	*/
 
 #if defined(__unix__)

src/sbbs3/xtrn.cpp

@@ -1911,7 +1911,7 @@ int sbbs_t::external(const char* cmdline, long mode, const char* startup_dir)
 				timeout.tv_sec=0;
 				timeout.tv_usec=1000;
 			}
-			if(i)
+			if(i && !(mode&EX_NOLOG))
 				lprintf(LOG_NOTICE,"%.*s",i,buf);		/* lprintf mangles i? */
 
 			/* Eat stderr if mode is EX_BIN */