diff --git a/src/cmd/ed1.s b/src/cmd/ed1.s
index 63d15ca..3210d09 100644
--- a/src/cmd/ed1.s
+++ b/src/cmd/ed1.s
@@ -26,7 +26,7 @@
    dzm fbuf
    lac d1
    dac dskadr
-   dac wrlfg
+   dac wrflg
    dzm diskin
  "o------------> [scan markup]
    jmp advanc
@@ -272,7 +272,7 @@ cw:
    jms putsc; tal1
 1:
    -1
-   tad tufp
+   tad tbufp
    cma
    tad tal1
    dac 1f
@@ -283,7 +283,7 @@ cw:
    jms number
    jmp advanc
 
-cn1:
+cnl:
    lac adrflg
    sna
    jmp 1f
@@ -346,7 +346,7 @@ addres: 0
 ad1:
    jms getsc; tal
 ad2:
-   jms betwen; d47; d56
+   jms betwen; d47; d58
    skp
    jmp numb
    sad o40 "[o40 circled in scan]
@@ -523,7 +523,7 @@ gline: 0
    dac glint1
    jms getdsk
    lac glint1 " [these 6 lines were surrounded by a box
-   adn o17777 " that was Xed out with an arrow pointing to it]:
+   and o17777 " that was Xed out with an arrow pointing to it]:
    tad dskbfp " --
    dac ital   "|\/|
    lac linep  "|/\|<---
diff --git a/src/cmd/ed2.s b/src/cmd/ed2.s
index 3345e98..458491a 100644
--- a/src/cmd/ed2.s
+++ b/src/cmd/ed2.s
@@ -3,7 +3,7 @@
 " ed2
 
 cs:
-   jsm getsc; tal
+   jms getsc; tal
    sad o40
    jmp cs
    sad o12
@@ -67,7 +67,7 @@ cs:
    jmp 3b
 3:
    -1
-   tad lcrhno
+   tad lchrno
    rcr
    szl
    xor o400000
@@ -118,7 +118,7 @@ bsrch:
    jms compile
    jms srcsav
    lac dot
-   dad zerop
+   sad zerop
    lac eofp
 bloop:
    tad dm1
@@ -275,7 +275,7 @@ execute: 0
    dac i trvect+1
    jmp 1f
 
-exchg: "???
+xchg: "???
    lacq
    sad o12
    jmp i execute
@@ -310,7 +310,7 @@ matchar: 0 "???
    skp
    jmp 1f
    lac matchar
-   adn o17777
+   and o17777
    tad jms1
    dac i 8 "??? [unreadable page cutoff]
 "** 08-rest.pdf page 26
@@ -407,7 +407,7 @@ matclo: 0 "???
 
 "??? the remainder of this scan had an unreadable first character
 "??? I did the best I could to recreate the characters appropriately
-o1: 1
+d1: 1
 o133: 0133
 dm3: -3
 o136: 0136
@@ -456,7 +456,7 @@ o54: 054
 o17: 017
 
 tname:
-   0145056;0164155;0160040;040040
+   0145056;0164155;0160040;040040	" e.tmp
 tbufp: tbuf
 linep: line
 nlistp: nlist
@@ -480,7 +480,7 @@ c1: .=.+1
 ital: .=.+1
 otal: .=.+1
 diskin: .=.+1
-glint: .=.+1
+glint1: .=.+1
 c2: .=.+1
 num: .=.+1
 zermp: .=.+1
@@ -502,7 +502,7 @@ bett1: .=.+1
 bett2: .=.+1
 wrflg: .=.+1
 apt1: .=.+1
-"[page cuts off one label]
+sfi: .=.+1			"[page cuts off one label] PLB: added
 "** 08-rest.pdf page 29
 "[handwritten page number top right of scan - 22]
 sfo: .=.+1
@@ -513,7 +513,7 @@ fbuf: .=.+4  "not sure if this is fbuf, but
 tbuf: .=.+64 "there is a write; tbuf; 64 call
 line: .=.+64
 nlist: .=.+50
-"??? ?list: .=.+50, unable to determine label
+clist: .=.+50		" unable to determine label [PLB missing clist]
 compbuf: .=.+100
 dskbuf: .=.+1 "[line crossed out - scan markup]
 lnodes: .=.+1000
diff --git a/tools/b.c b/tools/b.c
new file mode 100644
index 0000000..4fc4556
--- /dev/null
+++ b/tools/b.c
@@ -0,0 +1,895 @@
+// b.c - B compiler for PDP-7 Unix
+//
+// Implemented in a subset of the C language compatible with B.
+// Coding style and organization based on lastc1120c.c
+//
+// (C) 2016 Robert Swierczek, GPL3
+//
+
+// Just enough working to compile hello.b:
+//    gcc -m32 -Wno-multichar b.c -o b
+//    ./b hello.b hello.s
+//    perl as7 --out a.out bl.s hello.s bi.s
+//    perl a7out a.out
+
+#ifdef _WIN32
+#include <io.h>
+#else
+#include <unistd.h>
+#endif
+#include <stdio.h>
+#include <stdlib.h>
+#include <memory.h>
+#include <fcntl.h>
+#define eof xeof
+
+int fin = 0;
+int fout = 1;
+
+int symtab[500] = { /* , type = 1, value = 1, name = 4 */
+  1, 5,0,0,'a','u','t','o',0,
+  1, 6,0,0,'e','x','t','r','n',0,
+  1,10,0,0,'g','o','t','o',0,
+  1,11,0,0,'r','e','t','u','r','n',0,
+  1,12,0,0,'i','f',0,
+  1,13,0,0,'w','h','i','l','e',0,
+  1,14,0,0,'e','l','s','e',0,
+  0
+};
+
+int ctab[] = {
+    0,127,127,127,  0,127,127,127, /* NUL SOH STX ETX EOT ENQ ACK BEL */
+  127,126,126,127,127,127,127,127, /* BS  TAB LF  VT  FF  CR  SO  SI  */
+  127,127,127,127,127,127,127,127, /* DLE DC1 DC2 DC3 DC4 NAK SYN ETB */
+  127,127,127,127,127,127,127,127, /* CAN EM  SUB ESC FS  GS  RS  US  */
+  126, 34,122,127,127, 44, 47,121, /* SPC  !   "   #   $   %   &   '  */
+    6,  7, 42, 40,  9, 41,127, 43, /*  (   )   *   +   ,   -   .   /  */
+  124,124,124,124,124,124,124,124, /*  0   1   2   3   4   5   6   7  */
+  124,124,  8,  1, 63, 80, 65, 90, /*  8   9   :   ;   <   =   >   ?  */
+  127,123,123,123,123,123,123,123, /*  @   A   B   C   D   E   F   G  */
+  123,123,123,123,123,123,123,123, /*  H   I   J   K   L   M   N   O  */
+  123,123,123,123,123,123,123,123, /*  P   Q   R   S   T   U   V   W  */
+  123,123,123,  4,127,  5, 48,127, /*  X   Y   Z   [   \   ]   ^   _  */
+  127,123,123,123,123,123,123,123, /*  `   a   b   c   d   e   f   g  */
+  123,123,123,123,123,123,123,123, /*  h   i   j   k   l   m   n   o  */
+  123,123,123,123,123,123,123,123, /*  p   q   r   s   t   u   v   w  */
+  123,123,123,  2, 48,  3,127,127, /*  x   y   z   {   |   }   ~  DEL */
+};
+
+/* storage */
+
+int symbuf[10];
+int peeksym = -1;
+int peekc = 0;
+int eof = 0;
+int line = 1;
+int *csym = 0;
+int cval = 0;
+int isn = 1;
+int nerror = 0;
+
+int main(int argc, char **argv) {
+  if (argc > 1) {
+    if (argc > 2) {
+      if ((fout = creat(argv[2], 0777))<0) {
+        error('fo');
+        exit(1);
+      }
+    }
+    if ((fin = open(argv[1],0))<0) {
+      error('fi');
+      exit(1);
+    }
+  }
+
+  while (!eof) {
+    extdef();
+//    blkend();
+  }
+  xflush();
+  
+  exit(nerror);
+}
+
+int *lookup() {
+  int *np, *sp, *rp;
+ 
+  rp = symtab;
+  while (*rp) {
+    np = rp + 4;
+    sp = symbuf;
+    while (*np==*sp) {
+      if (!*np)
+        return rp;
+      np = np + 1;
+      sp = sp + 1;
+    }
+    while (*np)
+      np = np + 1;
+    rp = np + 1;
+  }
+  sp = symbuf;
+  np = rp + 4;
+  if (np >= symtab + 490) {
+    error("sf");
+    exit(1);
+  }
+loop:
+  *np = *sp;
+  np = np + 1;
+  sp = sp + 1;
+  if (*sp)
+    goto loop;
+  *np = 0;
+  return rp;
+}
+
+symbol() {
+//  extern peeksym, peekc, eof, xread, subseq, error, line;
+//  extern *csym, symbuf[], namsiz, lookup[], ctab, cval;
+//  auto b, c, ct;
+// char symbuf[], sp[], ctab[];
+  int b, c, ct;
+  int *sp;
+
+  if (peeksym>=0) {
+    c = peeksym;
+    peeksym = -1;
+    return(c);
+  }
+  if (peekc) {
+    c = peekc;
+    peekc = 0;
+  } else {
+    if (eof)
+      return(0);
+  else
+      c = xread();
+  }
+loop:
+  ct = ctab[c];
+ 
+  if (ct==0) { /* EOT */
+    eof++;
+    return(0);
+  }
+ 
+  if (ct==126) { /* white space */
+    if (c=='\n')  /* newline */
+      line = line + 1;
+    c = xread();
+    goto loop;
+  }
+
+  if (c=='=') {
+    return(subseq('=',80,60));
+  }
+  if (c=='<') {
+    return(subseq('=',63,62));
+  }
+  if (c=='>') {
+    return(subseq('=',65,64));
+  }
+  if (c=='!') {
+    return(subseq('=',34,61));
+  }
+  if (c=='$') {
+    if (subseq('(',0,1))
+      return(2);
+    if (subseq(')',0,1))
+      return(3);
+  }
+  if (c=='/') {
+    if (subseq('*',1,0))
+      return(43);
+com:
+    c = xread();
+com1:
+    if (c==4) {
+      eof++;
+      error('*/'); /* end of text */
+      return(0);
+    }
+    if (c=='\n')
+      line++;
+    if (c!='*')
+      goto com;
+    c = xread();
+    if (c!='/')
+      goto com1;
+    c = xread();
+    goto loop;
+  }
+  if (ct==124) {    /* number */
+    cval = 0;
+    if (c=='0')
+      b = 8;
+    else
+      b = 10;
+    while(c >= '0' && c <= '9') {
+      cval = cval*b + c -'0';
+      c = xread();
+    }
+    peekc = c;
+    return(21);
+  }
+  if (c=='\'') {    /* ' */
+    getcc();
+    return(21);
+  }
+  if (ct==123) {    /* letter */
+    sp = symbuf;
+    while(ctab[c]==123 | ctab[c]==124) {
+      if (sp<symbuf+9) *sp++ = c;
+      c = xread();
+    }
+    *sp = '\0';
+    peekc = c;
+    csym = lookup();
+    if (csym[0]==1) {    /* keyword */
+      cval = csym[1];
+      return(19);
+    }
+    return(20);
+  }
+  if (ct==127) {    /* unknown */
+    error('sy');
+    c = xread();
+    goto loop;
+  }
+  return(ctab[c]);
+}
+
+subseq(c,a,b) {
+  extern peekc; //    extern xread, peekc;
+ 
+  if (!peekc)
+    peekc = xread();
+  if (peekc != c)
+    return(a);
+  peekc = 0;
+  return(b);
+}
+
+getcc() {
+  extern cval;
+  auto c;
+
+  cval = 0;
+  if ((c = mapch('\'')) < 0) return;
+  cval = c;
+  if ((c = mapch('\'')) < 0) return;
+  cval = cval * 512 + c;
+  if ((c = mapch('\'')) >= 0)
+  error('cc');
+}
+
+mapch(c) {
+  extern peekc, line;
+  auto a;
+
+  if((a=xread())==c)
+    return(-1);
+ 
+  if (a=='\n' | a==0 | a==4) {
+    error('cc');
+    peekc = a;
+    return(-1);
+  }
+
+  if (a=='*') {
+    a=xread();
+
+    if (a=='0')
+      return('\0');
+
+    if (a=='e')
+      return(4);
+
+    if (a=='(')
+      return('{');
+
+    if (a==')')
+      return('}');
+
+    if (a=='t')
+      return('\t');
+
+    if (a=='r')
+      return('\r');
+
+    if (a=='n')
+      return('\n');
+  }
+  return(a);
+}
+
+void expr(int lev) {
+  int o;
+
+  o = symbol();
+  
+  if (o==21) { /* constant */
+case21:
+    gen('n',5); /* litrl */
+    xwrite(' ');
+    number(cval); 
+    xwrite('\n');
+    goto loop;
+  }
+   
+  if (o==20) { /* name */
+		if (*csym==0) {
+			if((peeksym=symbol())==6) { /* ( */
+				*csym = 6;	/* extern */
+      }
+			else {
+				if(csym[2]==0)	/* unseen so far */
+					csym[2] = isn++;
+			}
+    }
+		if(*csym==6)	/* extern */
+      gens('x',csym+4);
+		else
+      gen('a',csym+4);
+    goto loop;
+  }
+  
+  if (o==34) { /* ! */
+    expr(1);
+    gen('u',4); /* unot */
+    goto loop;
+  }
+
+  if (o==41) { /* - */
+    peeksym = symbol();
+    if (peeksym==21) { /* constant */
+      peeksym = -1;
+      cval = -cval;
+      goto case21;
+    }
+    expr(1);
+    gen('u',2); /* umin */
+    goto loop;
+  }
+  
+  if (o==47) { /* & */
+    expr(1);
+    gen('u',1); /* uadr */
+    goto loop;
+  }
+  
+  if (o==42) { /* * */
+    expr(1);
+    gen('u',3); /* uind */
+    goto loop;
+  }
+  
+  if (o==6) { /* ( */
+    peeksym = o;
+    pexpr();
+    goto loop;
+  }
+  error('ex');
+
+loop:
+  o = symbol();
+
+  if (lev>=14 & o==80) { /* = */
+    expr(14);
+    gen('b',1); /* asg */
+    goto loop;
+  }
+  if (lev>=10 & o==48) { /* | ^ */
+    expr(9);
+    gen('b',2); /* bor */
+    goto loop;
+  }
+  if (lev>=8 & o==47) { /* & */
+    expr(7);
+    gen('b',3); /* band */
+    goto loop;
+  }
+  if (lev>=7 & o>=60 & o<=61) {  /* == != */
+    expr(6);
+    gen('b',o-56); /* beq bne */
+    goto loop;
+  }
+  if (lev>=6 & o>=62 & o<=65) {  /* <= < >= > */
+    expr(5);
+    gen('b',o-56); /* ble blt bge bgt */
+    goto loop;
+  }  
+  if (lev>=4 & o>=40 & o<=41) {  /* + - */
+    expr(3);
+    gen('b',o-28); /* badd bmin */
+    goto loop;
+  }  
+  if (lev>=3 & o>=42 & o<=43) {  /* * / */
+    expr(2);
+    gen('b',o-27); /* bmul bdiv */
+    goto loop;
+  }  
+  if (lev>=3 & o==44) {  /* % */
+    expr(2);
+    gen('b',14); /* bmod */
+    goto loop;
+  }  
+  if (o==4) { /* [ */
+    expr(15);
+    if (symbol() != 5)
+      error('[]');
+    gen('b',12); /* badd */
+    gen('u',3); /* uind */
+    goto loop;
+  }
+  if (o==6) { /* ( */
+    o = symbol();
+    if (o==7) /* ) */
+      gen('n',1); /* mcall */
+    else {
+      gen('n',2); /* mark */
+      peeksym = o;
+      while (o!=7) {
+        expr(15);
+        o = symbol();
+        if (o!=7 && o!=9) { /* ) , */
+          error('ex');
+          return;
+        }
+      }
+      gen('n',3);
+    }
+    goto loop;
+  }
+  
+  peeksym = o;
+}
+
+#if 0
+
+decl(kw) {
+  extern csym[], symbol, paraml[], parame[];
+  extern error, cval, peeksym, exit;
+  int t[], n, o;
+
+  while((o=symbol())==20) {        /* name */
+    if(kw>=5) {            /* type or sort? */
+      if(*csym>0)
+        error('rd'); //error("%p redeclared", csym[4]);
+      *csym = kw;
+    } else {
+      if ((csym[1]&017)!=0)
+        error('rd'); //error("%p redeclared", &csym[4]);
+      csym[1] =| csym[1]&0760 | kw;
+      if (*csym==0)
+        *csym = -2;
+    }
+    while((o=symbol())==4) {    /* [ */
+      if((o=symbol())==21) {    /* const */
+        if(csym[1]>=020)
+          error('de'); //error("Bad vector");
+        csym[3] = cval;
+        o = symbol();
+      }
+      if (o!=5)        /* ] */
+        goto syntax;
+      csym[1] =+ 020;
+    }
+    if(kw==8)  {        /* parameter */
+      *csym = -1;
+      if (paraml==0)
+        paraml = csym;
+      else
+        *parame = csym;
+      parame = csym;
+    }
+    if (o!=9)    /* , */
+      break;
+  }
+  if(o==1 & kw!=8 | o==7 & kw==8)
+    return;
+syntax:
+  error('[]'); //error("Declaration syntax");
+}
+#endif
+
+function() {
+//  extern declare, blkhed, blkend;
+//  extern printf, statement, peeksym, cval, symbol;
+//  extern paraml;
+//  auto o;
+
+//  printf(".text; 1:mov r5,-(sp); mov sp,r5\n");
+//  declare(8);
+//  declist();
+  gen('s',2); /* ??? */
+  statement(1);
+  gen('n',7); /* retrn */
+}
+
+
+extdef() {
+//  extern eof, function, cval;
+//  extern symbol, block, printf, pname, csym[];
+//  extern error;
+  auto o, c, *cs;
+//  char s;
+
+  o = symbol();
+  if(o==0 | o==1)    /* EOF */
+    return;
+
+  if(o!=20)
+    goto syntax;
+
+  csym[0] = 6;
+  cs = csym + 4;
+  xwrite('.');
+  name(cs);
+  xwrite(': ');
+  xwrite('.+');
+  xwrite('1\n');
+//  s = ".data; %p:1f\n";
+  o=symbol();
+  
+  if (o==6) { /* ( */
+    function();
+    return;
+  }
+
+  if (o==2) { /* $( */
+    peeksym = o;
+    function();
+    return;
+  }
+  
+  if (o==21) { /* const */
+    printf(".data; %p: %o\n", cs, cval);
+    if((o=symbol())!=1)    /* ; */
+      goto syntax;
+    return;
+  }
+  
+  if (o==1) { /* ; */
+    printf(".bss; %p: .=.+2\n", cs);
+    return;
+  }
+  
+  if (o==4) { /* [ */
+    c = 0;
+    if((o=symbol())==21) {    /* const */
+      c = cval<<1;
+      o = symbol();
+    }
+    if(o!=5)        /* ] */
+      goto syntax;
+    if((o=symbol())==1) {    /* ; */
+      printf(".bss; 1:.=.+%o\n", c);
+      return;
+    }
+    printf("1:");
+    while(o==21) {        /* const */
+      printf("%o\n", cval);
+      c =- 2;
+      if((o=symbol())==1)    /* ; */
+        goto done;
+      if(o!=9)        /* , */
+        goto syntax;
+      else
+        o = symbol();
+    }
+    goto syntax;
+done:
+    if(c>0)
+      printf(".=.+%o\n", c);
+    return;
+  }
+  
+  if (o==0) /* EOF */
+    return;
+
+syntax:
+  error('xx');
+  statement(0);
+}
+
+statement(d) {
+//  extern symbol, error, blkhed, eof, peeksym;
+//  extern blkend, csym[], rcexpr, block[], tree[], regtab[];
+//  extern jumpc, jump, label, contlab, brklab, cval;
+//  extern swp[], isn, pswitch, peekc, slabel;
+//  extern efftab[], declare, deflab, swtab[], swsiz, branch;
+
+//  int o, o1, o2, np[];
+  int o, o1, o2, n, *np;
+
+stmt:
+  o = symbol();
+  
+  if (o==0) /* EOF */
+  {
+    error('fe'); //"Unexpected EOF");
+    return;
+  }
+  
+  if (o==1 || o==3) /* ; } */
+    return;
+  
+  if (o==2) { /* { */
+    if(d)
+      blkhed();
+    while (!eof) {
+      o = symbol();
+      if (o==3) /* } */
+        return;
+      peeksym = o;
+      statement(0);
+    }
+    error('$)'); //error("Missing '}'");
+    return;
+  }
+
+  if (o==19) { /* keyword */
+
+#if 0
+    
+    if (cval==10) { /* goto */
+      o1 = block(1,102,0,0,tree());
+//      rcexpr(o1, regtab);
+      goto semi;
+  }
+#endif
+    
+    if (cval==11) { /* return */
+      if((peeksym=symbol())==6)    /* ( */
+        pexpr();
+      gen('n',7); /* retrn */
+      goto semi;
+    }
+    
+    if (cval==12) { /* if */
+      pexpr();
+      o1 = isn;
+      isn++;
+      jumpc(o1);
+      statement(0);
+      o = symbol();
+      if (o==19 & cval==14) { /* else */
+        o2 = isn;
+        isn++;
+        jump(o2);
+        label(o1);
+        statement(0);
+        label(o2);
+        return;
+      }
+      peeksym = o;
+      label(o1);
+      return;
+    }
+
+    if (cval==13) {  /* while */
+      o1 = isn;
+      isn++;
+      label(o1);
+      pexpr();
+      o2 = isn;
+      isn++;
+      jumpc(o2);
+      statement(0);
+      jump(o1);
+      label(o2);
+      return;
+    }
+
+    error('sx');
+    goto syntax;
+  }
+
+  if (o==20) { /* name */
+#if 0
+    if (peekc==':') {
+      peekc = 0;
+      if (csym[0]>0) {
+        error('rd');
+        goto stmt;
+      }
+      csym[0] = 2;
+      csym[1] = 020;    /* int[] */
+//      if (csym[2]==0)
+//        csym[2] = isn++;
+      slabel();
+      goto stmt;
+    }
+#endif
+  }
+
+  peeksym = o;
+  expr(15);
+
+semi:
+  o = symbol();
+  if (o==1)        /* ; */
+    return;
+
+syntax:
+  error('sz');
+  goto stmt;
+}
+
+pexpr()
+{
+  auto o, t;
+
+  if ((o=symbol())==6) { /* ( */
+    expr(15);
+    if ((o=symbol())==7) /* ) */
+      return;
+  }
+  error('()');
+}
+
+blkhed()
+{
+#if 0
+    extern symbol, cval, declare, peeksym, paraml[], parame[];
+    extern error, length, rlength, setstk, defvec, isn, defstat;
+    extern stack, hshtab[], hshsiz, pssiz;
+    int o, al, pl, cs[], hl;
+
+    declist();
+    stack = al = -2;
+    pl = 4;
+    while(paraml) {
+        *parame = 0;
+        paraml = *(cs = paraml);
+        cs[2] = pl;
+        *cs = 10;
+        pl =+ rlength(cs[1]);
+    }
+    cs = hshtab;
+    hl = hshsiz;
+    while(hl--) {
+        if (cs[4])
+        switch(cs[0]) {
+
+        /* sort unmentioned */
+        case 0177776:    /* -2 */
+            cs[0] = 5;        /* auto */
+
+        /* auto */
+        case 5:
+            if (cs[3]) {    /* vector */
+                al =- (cs[3]*length(cs[1]-020)+1) & 077776;
+                setstk(al);
+                defvec(al);
+            }
+            cs[2] = al;
+            al =- rlength(cs[1]);
+            goto loop;
+
+        /* parameter */
+        case 10:
+            cs[0] = 5;
+            goto loop;
+
+        /* static */
+        case 7:
+            cs[2] = isn++;
+            defstat(cs);
+            goto loop;
+
+        loop:;
+        }
+        cs = cs+pssiz;
+    }
+    setstk(al);
+#endif
+}
+
+gens(o,n) {
+  xwrite(' ');
+  xwrite(o);
+  xwrite(' .');
+  name(n);
+  xwrite('\n');
+}
+
+gen(o,n) {
+  xwrite(' ');
+  xwrite(o);
+  xwrite(' ');
+  number(n);
+  xwrite('\n');
+}
+
+jumpc(n) {
+  xwrite(' f'); /* ifop */
+  xwrite(' .');
+  number(n);
+  xwrite('\n');
+}
+
+jump(lbl) {
+  xwrite(' t'); /* traop */
+  xwrite(' .');
+  number(lbl);
+  xwrite('\n');
+}
+
+label(lbl) {
+  xwrite('.');
+  number(lbl);
+  xwrite(': ');
+  xwrite('t ');
+  xwrite('.+');
+  xwrite('1\n');
+}
+
+printn(n) {
+  if (n > 9) {
+    printn(n / 10);
+    n = n % 10;
+  }
+  xwrite(n + '0');
+}
+
+number(x) {
+  if (x < 0) {
+    xwrite('-');
+    x = -x;
+  }
+  printn(x);
+}
+
+name(int *s) {
+  while (*s) {
+    xwrite(*s);
+    s = s + 1;
+  }
+}
+
+error(code)
+{
+  extern line;
+  int f;
+  
+  nerror++;
+  xflush();
+  f = fout;
+  fout = 1;
+  xwrite(code);
+  xwrite(' ');
+  if (code=='rd' | code=='un') {
+    name(csym + 4);
+    xwrite(' ');
+  }
+  printn(line);
+  xwrite('\n');
+  fout = f;
+}
+
+// runtime:
+
+xread() {
+  char buf[1];
+  if (read(fin, buf, 1) <= 0)
+  return 4;
+  return buf[0];
+}
+
+xwrite(int c) {
+  char buf[2];
+  if (c & 0xff00) {
+    buf[0] = (c >> 8) & 0xff;
+    buf[1] = c & 0xff;
+    write(fout, buf, 2);
+  } else {
+    buf[0] = c & 0xff;
+    write(fout, buf, 1);
+  }
+}
+
+xflush() {
+}
\ No newline at end of file