SCP: Add a "-N" (new file) option to the SET LOG and SET DEBUG commands. From Dave Bryan.

scp.c

@@ -970,6 +970,9 @@ static const char simh_help[] =
       "+set log log_file            specify the log destination\n"
       "++++++++                     (STDOUT,DEBUG or filename)\n"
       "+set nolog                   disables any currently active logging\n"
+      "4Switches\n"
+      " By default, log output is written at the end of the specified log file.\n"
+      " A new log file can created if the -N switch is used on the command line.\n"
 #define HLP_SET_DEBUG  "*Commands SET Debug"
        /***************** 80 character line width template *************************/
       "3Debug\n"
@@ -994,6 +997,9 @@ static const char simh_help[] =
       "5-P\n"
       " The -P switch adds the output of the PC (Program Counter) to each debug\n"
       " message.\n"
+      "5-N\n"
+      " The -N switch causes a new/empty file to be written to.  The default\n"
+      " is to append to an existing debug log file.\n"
 #define HLP_SET_BREAK  "*Commands SET Breakpoints"
       "3Breakpoints\n"
       "+set break <list>            set breakpoints\n"

sim_console.c

@@ -1612,7 +1612,10 @@ else {
         return SCPE_MEM;
     get_glyph_nc (filename, gbuf, 0);                   /* reparse */
     strncpy ((*pref)->name, gbuf, sizeof((*pref)->name)-1);
-    *pf = sim_fopen (gbuf, (binary ? "a+b" : "a+"));    /* open file */
+    if (sim_switches & SWMASK ('N'))                    /* if a new log file is requested */
+        *pf = sim_fopen (gbuf, (binary ? "w+b" : "w+"));/*   then open an empty file */
+    else                                                /* otherwise */
+        *pf = sim_fopen (gbuf, (binary ? "a+b" : "a+"));/*   append to an existing file */
     if (*pf == NULL) {                                  /* error? */
         free (*pref);
         *pref = NULL;