tools/a7out: I took out the code to pretend to deal with binary files,

and I did a perltidy to reformat the code.

tools/a7out

@@ -37,7 +37,8 @@ while ( defined( $ARGV[0] ) && ( $ARGV[0] =~ m{^-} ) ) {
 
     # -d: debug mode
     if ( $ARGV[0] eq "-d" ) {
-        $debug = 1; shift(@ARGV);
+        $debug = 1;
+        shift(@ARGV);
     }
 
     # -b: set a breakpoint
@@ -248,14 +249,7 @@ sub add {
     my ( $instruction, $addr, $indaddr ) = @_;
     dprintf( "add AC (value %06o) with addr %06o (%06o)\n",
         $AC, $indaddr, $Mem[$indaddr] );
-#    $LINK = 0;
+
-#    $AC   = $AC + $Mem[$indaddr];
-#    if ( $AC & LINKMASK ) {
-#        $AC++;    # End-around carry
-#        $LINK = LINKMASK;
-#    }
-#    $AC = $AC & MAXINT;
-#
     # This logic shamelessly borrowed from SimH
     # https://github.com/simh/simh/blob/master/PDP18B/pdp18b_cpu.c
     my $sum = $AC + $Mem[$indaddr];
@@ -266,7 +260,6 @@ sub add {
         $LINK = LINKMASK;                                   # set link
     }
     $AC = $sum;
-
     $PC++;
 }
 
@@ -350,10 +343,12 @@ sub opr {
     }
 
     # List of skip opcode names for the next section
-    my @skipop= ( '', 'sma', 'sza', 'sza sma',
+    my @skipop = (
+        '',    'sma',     'sza',     'sza sma',
         'snl', 'snl sma', 'snl sza', 'snl sza sma',
         'skp', 'spa',     'sna',     'sna spa',
-		'szl', 'szl spa', 'szl sna', 'szl sna spa');
+        'szl', 'szl spa', 'szl sna', 'szl sna spa'
+    );
 
     # This logic shamelessly borrowed from SimH
     # https://github.com/simh/simh/blob/master/PDP18B/pdp18b_cpu.c
@@ -363,23 +358,29 @@ sub opr {
 
     $skip = 1 if ( ( $i == 1 ) && ( $AC & SIGN ) != 0 );      # sma
     $skip = 1 if ( ( $i == 2 ) && ( $AC & MAXINT ) == 0 );    # sza
-    $skip=1 if (($i == 3) && 
+    $skip = 1 if ( ( $i == 3 )
-           ((($AC & MAXINT) == 0) || (($AC & SIGN) != 0)));	# sza | sma
+        && ( ( ( $AC & MAXINT ) == 0 ) || ( ( $AC & SIGN ) != 0 ) ) )
+      ;                                                       # sza | sma
     $skip = 1 if ( ( $i == 4 ) && ($LINK) );                         # snl
     $skip = 1 if ( ( $i == 5 ) && ( $LINK || ( $AC >= SIGN ) ) );    # snl | sma
     $skip = 1 if ( ( $i == 6 ) && ( $LINK || ( $AC == 0 ) ) );       # snl | sza
-    $skip=1 if (($i == 7) &&
+    $skip = 1 if ( ( $i == 7 )
-            ($LINK || ($AC >= SIGN) || ($AC == 0)));	# snl | sza | sma
+        && ( $LINK || ( $AC >= SIGN ) || ( $AC == 0 ) ) );    # snl | sza | sma
     $skip = 1 if ( $i == 010 );                                     # skp
     $skip = 1 if ( ( $i == 011 ) && ( ( $AC & SIGN ) == 0 ) );      # spa
     $skip = 1 if ( ( $i == 012 ) && ( ( $AC & MAXINT ) != 0 ) );    # sna
-    $skip=1 if (($i == 013) &&
+    $skip = 1 if ( ( $i == 013 )
-            (($AC & MAXINT) != 0) && (($AC & SIGN) == 0)); # sna & spa
+        && ( ( $AC & MAXINT ) != 0 )
+        && ( ( $AC & SIGN ) == 0 ) );                               # sna & spa
     $skip = 1 if ( ( $i == 014 ) && ( $LINK == 0 ) );               # szl
-    $skip=1 if (($i == 015) && ($LINK == 0) && ($AC < SIGN));		# szl & spa
+    $skip = 1
-    $skip=1 if (($i == 016) && ($LINK == 0) && ($AC != 0));		# szl & sna
+      if ( ( $i == 015 ) && ( $LINK == 0 ) && ( $AC < SIGN ) );     # szl & spa
-    $skip=1 if (($i == 017) &&
+    $skip = 1
-		($LINK == 0) && ($AC != 0) && ($AC != 0)); 	# szl & sna & spa
+      if ( ( $i == 016 ) && ( $LINK == 0 ) && ( $AC != 0 ) );       # szl & sna
+    $skip = 1 if ( ( $i == 017 )
+        && ( $LINK == 0 )
+        && ( $AC != 0 )
+        && ( $AC != 0 ) );    # szl & sna & spa
 
     # Clear operations
     if ( $instruction & 010000 ) {    # cla
@@ -389,10 +390,12 @@ sub opr {
         dprintf(" cli"); $LINK = 0;
     }
     if ( $instruction & 000002 ) {    # cmi
-	dprintf(" cmi"); $LINK= ($LINK) ? 0 : LINKMASK;
+        dprintf(" cmi");
+        $LINK = ($LINK) ? 0 : LINKMASK;
     }
     if ( $instruction & 000001 ) {    # cma
-	dprintf(" cma"); $AC= ($AC ^ MAXINT) & MAXINT;
+        dprintf(" cma");
+        $AC = ( $AC ^ MAXINT ) & MAXINT;
     }
 
     # Rotate instructions
@@ -477,7 +480,6 @@ sub eae {
 
         # Save the AC's sign into LINK
         my $newlink = ( $AC << 1 ) & LINKMASK;
-
         $AC = ( ( $LINK | $AC ) >> $step ) & MAXINT;
         $LINK = $newlink;
         $PC++;
@@ -486,7 +488,6 @@ sub eae {
     if ( $instruction == 0660700 ) {    # alss: long left shift, signed
                                         # We don't fill the lsb with LINK yet
         dprintf( "alss %06o AC step %d\n", $AC, $step );
-
         $AC = ( $AC << $step ) & MAXINT;
         $PC++;
         return;
@@ -526,6 +527,7 @@ sub sys_close {
 
 # Open system call
 sub sys_open {
+
     # Open seems to have 2 arguments: PC+1 is a pointer to the filename.
     # PC+2 seems to be 1 for write, 0 for read.
     # Some programs seem to have a third argument always set to 0.
@@ -595,22 +597,12 @@ sub sys_read {
     $count = 0;
     foreach my $addr ( $start .. $end ) {
 
-        # It's a terminal, so convert from ASCII
-        if ( -t $FH ) {
         my $c1 = getc($FH);
         last if ( !defined($c1) );    # No character, leave the loop
         my $c2 = getc($FH) || "";     # No character, make it a NUL
         $Mem[$addr] =
           ( ord($c1) << 9 ) | ord($c2);    # Pack both into one word
         $count++;
-        } else {
-            # otherwise (for now) read in one line and convert to octal
-            my $line = <$FH>;
-            last if ( !defined($line) );       # No line, leave the loop
-            chomp($line);
-            $Mem[$addr] = oct($line) & MAXINT;
-            $count++;
-        }
     }
 
     # No error
@@ -647,13 +639,7 @@ sub sys_write {
     my $FH = $FD[$fd];
     foreach my $addr ( $start .. $end ) {
 
-        # It's a terminal, so convert to ASCII
-        # otherwise (for now) print in octal
-        if ( -t $FH ) {
         print( $FH word2ascii( $Mem[$addr] ) );
-        } else {
-            printf( $FH "%06o\n", $Mem[$addr] );
-        }
     }
 
     # No error