--- stack/stack.c	2002/03/07 01:21:07	1.90
+++ stack/stack.c	2002/03/08 16:09:30	1.93
@@ -1,3 +1,25 @@
+/*
+    stack - an interactive interpreter for a stack-based language
+    Copyright (C) 2002	Mats Alritzson and Teddy Hogeborn
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+    Authors: Mats Alritzson <masse@fukt.bth.se>
+	     Teddy Hogeborn <teddy@fukt.bth.se>
+*/
+
 /* printf, sscanf, fgets, fprintf, fopen, perror */
 #include <stdio.h>
 /* exit, EXIT_SUCCESS, malloc, free */
@@ -8,12 +30,16 @@
 #include <dlfcn.h>
 /* strcmp, strcpy, strlen, strcat, strdup */
 #include <string.h>
-/* getopt, STDIN_FILENO, STDOUT_FILENO */
+/* getopt, STDIN_FILENO, STDOUT_FILENO, usleep */
 #include <unistd.h>
 /* EX_NOINPUT, EX_USAGE */
 #include <sysexits.h>
 /* mtrace, muntrace */
 #include <mcheck.h>
+/* ioctl */
+#include <sys/ioctl.h>
+/* KDMKTONE */
+#include <linux/kd.h>
 
 #include "stack.h"
 
@@ -92,15 +118,15 @@
   stackitem *nitem= malloc(sizeof(stackitem));
 
   nval->content.ptr= NULL;
-  protect(env, nval);
-
-  gc_init(env);
 
   nitem->item= nval;
   nitem->next= env->gc_ref;
   env->gc_ref= nitem;
 
   env->gc_count++;
+
+  protect(env, nval);
+  gc_init(env);
   unprotect(env);
 
   return nval;
@@ -125,31 +151,35 @@
 }
 
 extern void gc_init(environment *env) {
-  stackitem *new_head= NULL, *titem, *iterator= env->gc_ref;
+  stackitem *new_head= NULL, *titem, *iterator;
   symbol *tsymb;
   int i;
 
   if(env->gc_count < env->gc_limit)
     return;
 
+  /* Garb by default */
+  iterator= env->gc_ref;
   while(iterator!=NULL) {
     iterator->item->gc_garb= 1;
     iterator= iterator->next;
   }
 
-  /* Mark */
+  /* Mark protected values */
   iterator= env->gc_protect;
   while(iterator!=NULL) {
     gc_mark(iterator->item);
     iterator= iterator->next;
   }
 
+  /* Mark values in stack */
   iterator= env->head;
   while(iterator!=NULL) {
     gc_mark(iterator->item);
     iterator= iterator->next;
   }
 
+  /* Mark values in hashtable */
   for(i= 0; i<HASHTBLSIZE; i++) {
     tsymb= env->symbols[i];
     while(tsymb!=NULL) {
@@ -164,12 +194,12 @@
   while(env->gc_ref!=NULL) {
 
     if(env->gc_ref->item->gc_garb) {
-      switch(env->gc_ref->item->type) {
+
+      /* Remove content */
+      switch(env->gc_ref->item->type) {	
       case string:
 	free(env->gc_ref->item->content.ptr);
 	break;
-      case integer:
-	break;
       case list:
 	while(env->gc_ref->item->content.ptr!=NULL) {
 	  titem= env->gc_ref->item->content.ptr;
@@ -180,11 +210,11 @@
       default:
 	break;
       }
-      free(env->gc_ref->item);
+      free(env->gc_ref->item);	/* Remove from gc_ref */
       titem= env->gc_ref->next;
-      free(env->gc_ref);
+      free(env->gc_ref);	/* Remove value */
       env->gc_ref= titem;
-    } else {
+    } else {			/* Save */
       titem= env->gc_ref->next;
       env->gc_ref->next= new_head;
       new_head= env->gc_ref;
@@ -226,12 +256,22 @@
 {
   value *new_value= new_val(env);
   
-  new_value->content.val= in_val;
+  new_value->content.i= in_val;
   new_value->type= integer;
 
   push_val(env, new_value);
 }
 
+void push_float(environment *env, float in_val)
+{
+  value *new_value= new_val(env);
+
+  new_value->content.f= in_val;
+  new_value->type= tfloat;
+
+  push_val(env, new_value);
+}
+
 /* Copy a string onto the stack. */
 void push_cstring(environment *env, const char *in_string)
 {
@@ -302,6 +342,9 @@
   char *mangled;		/* Mangled function name */
 
   new_value= new_val(env);
+  protect(env, new_value);
+  new_fvalue= new_val(env);
+  protect(env, new_fvalue);
 
   /* The new value is a symbol */
   new_value->type= symb;
@@ -336,7 +379,6 @@
       dlerr= dlerror();
     }
     if(dlerr==NULL) {		/* If a function was found */
-      new_fvalue= new_val(env); /* Create a new value */
       new_fvalue->type= func;	/* The new value is a function pointer */
       new_fvalue->content.ptr= funcptr; /* Store function pointer */
       (*new_symbol)->val= new_fvalue; /* Bind the symbol to the new
@@ -344,6 +386,7 @@
     }
   }
   push_val(env, new_value);
+  unprotect(env); unprotect(env);
 }
 
 /* Print newline. */
@@ -367,6 +410,9 @@
   case integer:
     push_sym(env, "integer");
     break;
+  case tfloat:
+    push_sym(env, "float");
+    break;
   case string:
     push_sym(env, "string");
     break;
@@ -387,7 +433,10 @@
 {
   switch(stack_head->item->type) {
   case integer:
-    printf("%d", stack_head->item->content.val);
+    printf("%d", stack_head->item->content.i);
+    break;
+  case tfloat:
+    printf("%f", stack_head->item->content.f);
     break;
   case string:
     if(noquote)
@@ -571,10 +620,9 @@
   case list:
     temp_val= env->head->item;
     protect(env, temp_val);
-    toss(env);
-    if(env->err) return;
+
+    toss(env); if(env->err) return;
     iterator= (stackitem*)temp_val->content.ptr;
-    unprotect(env);
     
     while(iterator!=NULL) {
       push_val(env, iterator->item);
@@ -592,6 +640,7 @@
       }
       iterator= iterator->next;
     }
+    unprotect(env);
     return;
 
   default:
@@ -633,6 +682,8 @@
   value *pack;
 
   iterator= env->head;
+  pack= new_val(env);
+  protect(env, pack);
 
   if(iterator==NULL
      || (iterator->item->type==symb
@@ -650,18 +701,20 @@
     temp= env->head;
     env->head= iterator->next;
     iterator->next= NULL;
+
+    pack->type= list;
+    pack->content.ptr= temp;
     
     if(env->head!=NULL)
       toss(env);
   }
 
   /* Push list */
-  pack= new_val(env);
-  pack->type= list;
-  pack->content.ptr= temp;
 
   push_val(env, pack);
   rev(env);
+
+  unprotect(env);
 }
 
 /* Relocate elements of the list on the stack. */
@@ -739,7 +792,7 @@
     return;
   }
 
-  val= env->head->item->content.val;
+  val= env->head->item->content.i;
   toss(env);
   push_int(env, !val);
 }
@@ -903,6 +956,14 @@
     }
   }
 
+  if(myenv.interactive) {
+    printf("Stack version $Revision: 1.93 $\n\
+Copyright (C) 2002  Mats Alritzson and Teddy Hogeborn\n\
+Stack comes with ABSOLUTELY NO WARRANTY; for details type `warranty;'.\n\
+This is free software, and you are welcome to redistribute it\n\
+under certain conditions; type `copying;' for details.\n");
+  }
+
   while(1) {
     if(myenv.in_string==NULL) {
       if (myenv.interactive) {
@@ -917,7 +978,7 @@
     }
     sx_72656164(&myenv);
     if (myenv.err==4) {
-      return EX_NOINPUT;
+      return EXIT_SUCCESS;	/* EOF */
     } else if(myenv.head!=NULL
 	      && myenv.head->item->type==symb
 	      && ((symbol*)(myenv.head->item->content.ptr))->id[0]==';') {
@@ -933,6 +994,7 @@
 /* "+" */
 extern void sx_2b(environment *env) {
   int a, b;
+  float fa, fb;
   size_t len;
   char* new_string;
   value *a_val, *b_val;
@@ -957,26 +1019,62 @@
     push_cstring(env, new_string);
     unprotect(env); unprotect(env);
     free(new_string);
+    
     return;
   }
   
-  if(env->head->item->type!=integer
-     || env->head->next->item->type!=integer) {
-    printerr("Bad Argument Type");
-    env->err=2;
+  if(env->head->item->type==integer
+     && env->head->next->item->type==integer) {
+    a=env->head->item->content.i;
+    toss(env); if(env->err) return;
+    b=env->head->item->content.i;
+    toss(env); if(env->err) return;
+    push_int(env, b+a);
+
     return;
   }
-  a= env->head->item->content.val;
-  toss(env); if(env->err) return;
-  
-  b= env->head->item->content.val;
-  toss(env); if(env->err) return;
-  push_int(env, a+b);
+
+  if(env->head->item->type==tfloat
+     && env->head->next->item->type==tfloat) {
+    fa= env->head->item->content.f;
+    toss(env); if(env->err) return;
+    fb= env->head->item->content.f;
+    toss(env); if(env->err) return;
+    push_float(env, fb+fa);
+    
+    return;
+  }
+
+  if(env->head->item->type==tfloat
+     && env->head->next->item->type==integer) {
+    fa= env->head->item->content.f;
+    toss(env); if(env->err) return;
+    b= env->head->item->content.i;
+    toss(env); if(env->err) return;
+    push_float(env, b+fa);
+    
+    return;
+  }
+
+  if(env->head->item->type==integer
+     && env->head->next->item->type==tfloat) {
+    a= env->head->item->content.i;
+    toss(env); if(env->err) return;
+    fb= env->head->item->content.f;
+    toss(env); if(env->err) return;
+    push_float(env, fb+a);
+
+    return;
+  }
+
+  printerr("Bad Argument Type");
+  env->err=2;
 }
 
 /* "-" */
 extern void sx_2d(environment *env) {
   int a, b;
+  float fa, fb;
 
   if((env->head)==NULL || env->head->next==NULL) {
     printerr("Too Few Arguments");
@@ -984,23 +1082,58 @@
     return;
   }
   
-  if(env->head->item->type!=integer
-     || env->head->next->item->type!=integer) {
-    printerr("Bad Argument Type");
-    env->err=2;
+  if(env->head->item->type==integer
+     && env->head->next->item->type==integer) {
+    a=env->head->item->content.i;
+    toss(env); if(env->err) return;
+    b=env->head->item->content.i;
+    toss(env); if(env->err) return;
+    push_int(env, b-a);
+
     return;
   }
 
-  a=env->head->item->content.val;
-  toss(env); if(env->err) return;
-  b=env->head->item->content.val;
-  toss(env); if(env->err) return;
-  push_int(env, b-a);
+  if(env->head->item->type==tfloat
+     && env->head->next->item->type==tfloat) {
+    fa= env->head->item->content.f;
+    toss(env); if(env->err) return;
+    fb= env->head->item->content.f;
+    toss(env); if(env->err) return;
+    push_float(env, fb-fa);
+    
+    return;
+  }
+
+  if(env->head->item->type==tfloat
+     && env->head->next->item->type==integer) {
+    fa= env->head->item->content.f;
+    toss(env); if(env->err) return;
+    b= env->head->item->content.i;
+    toss(env); if(env->err) return;
+    push_float(env, b-fa);
+    
+    return;
+  }
+
+  if(env->head->item->type==integer
+     && env->head->next->item->type==tfloat) {
+    a= env->head->item->content.i;
+    toss(env); if(env->err) return;
+    fb= env->head->item->content.f;
+    toss(env); if(env->err) return;
+    push_float(env, fb-a);
+
+    return;
+  }
+
+  printerr("Bad Argument Type");
+  env->err=2;
 }
 
 /* ">" */
 extern void sx_3e(environment *env) {
   int a, b;
+  float fa, fb;
 
   if((env->head)==NULL || env->head->next==NULL) {
     printerr("Too Few Arguments");
@@ -1008,41 +1141,93 @@
     return;
   }
   
-  if(env->head->item->type!=integer
-     || env->head->next->item->type!=integer) {
-    printerr("Bad Argument Type");
-    env->err=2;
+  if(env->head->item->type==integer
+     && env->head->next->item->type==integer) {
+    a=env->head->item->content.i;
+    toss(env); if(env->err) return;
+    b=env->head->item->content.i;
+    toss(env); if(env->err) return;
+    push_int(env, b>a);
+
     return;
   }
 
-  a=env->head->item->content.val;
-  toss(env); if(env->err) return;
-  b=env->head->item->content.val;
-  toss(env); if(env->err) return;
-  push_int(env, b>a);
+  if(env->head->item->type==tfloat
+     && env->head->next->item->type==tfloat) {
+    fa= env->head->item->content.f;
+    toss(env); if(env->err) return;
+    fb= env->head->item->content.f;
+    toss(env); if(env->err) return;
+    push_int(env, fb>fa);
+    
+    return;
+  }
+
+  if(env->head->item->type==tfloat
+     && env->head->next->item->type==integer) {
+    fa= env->head->item->content.f;
+    toss(env); if(env->err) return;
+    b= env->head->item->content.i;
+    toss(env); if(env->err) return;
+    push_int(env, b>fa);
+    
+    return;
+  }
+
+  if(env->head->item->type==integer
+     && env->head->next->item->type==tfloat) {
+    a= env->head->item->content.i;
+    toss(env); if(env->err) return;
+    fb= env->head->item->content.f;
+    toss(env); if(env->err) return;
+    push_int(env, fb>a);
+
+    return;
+  }
+
+  printerr("Bad Argument Type");
+  env->err=2;
+}
+
+/* "<" */
+extern void sx_3c(environment *env) {
+  swap(env); if(env->err) return;
+  sx_3e(env);
+}
+
+/* "<=" */
+extern void sx_3c3d(environment *env) {
+  sx_3e(env); if(env->err) return;
+  not(env);
+}
+
+/* ">=" */
+extern void sx_3e3d(environment *env) {
+  sx_3c(env); if(env->err) return;
+  not(env);
 }
 
 /* Return copy of a value */
 value *copy_val(environment *env, value *old_value){
   stackitem *old_item, *new_item, *prev_item;
-
-  value *new_value= new_val(env);
+  value *new_value;
 
   protect(env, old_value);
+  new_value= new_val(env);
+  protect(env, new_value);
   new_value->type= old_value->type;
 
   switch(old_value->type){
+  case tfloat:
   case integer:
-    new_value->content.val= old_value->content.val;
+  case func:
+  case symb:
+    new_value->content= old_value->content;
     break;
   case string:
     (char *)(new_value->content.ptr)= 
       strdup((char *)(old_value->content.ptr));
     break;
-  case func:
-  case symb:
-    new_value->content.ptr= old_value->content.ptr;
-    break;
   case list:
     new_value->content.ptr= NULL;
 
@@ -1064,7 +1249,7 @@
     break;
   }
 
-  unprotect(env);
+  unprotect(env); unprotect(env);
 
   return new_value;
 }
@@ -1099,7 +1284,7 @@
   swap(env);
   if(env->err) return;
   
-  truth=env->head->item->content.val;
+  truth=env->head->item->content.i;
 
   toss(env);
   if(env->err) return;
@@ -1131,7 +1316,7 @@
   rot(env);
   if(env->err) return;
   
-  truth=env->head->item->content.val;
+  truth=env->head->item->content.i;
 
   toss(env);
   if(env->err) return;
@@ -1176,7 +1361,7 @@
       return;
     }
     
-    truth= env->head->item->content.val;
+    truth= env->head->item->content.i;
     toss(env); if(env->err) return;
     
     if(truth) {
@@ -1215,10 +1400,10 @@
   protect(env, loop);
   toss(env); if(env->err) return;
 
-  foo2= env->head->item->content.val;
+  foo2= env->head->item->content.i;
   toss(env); if(env->err) return;
 
-  foo1= env->head->item->content.val;
+  foo1= env->head->item->content.i;
   toss(env); if(env->err) return;
 
   if(foo1<=foo2) {
@@ -1295,9 +1480,9 @@
     return;
   }
 
-  ending= env->head->item->content.val;
+  ending= env->head->item->content.i;
   toss(env); if(env->err) return;
-  start= env->head->item->content.val;
+  start= env->head->item->content.i;
   toss(env); if(env->err) return;
 
   temp_head= env->head;
@@ -1312,10 +1497,14 @@
   }
 
   temp_val= new_val(env);
+  protect(env, temp_val);
+
   temp_val->content.ptr= env->head;
   temp_val->type= list;
   env->head= temp_head;
   push_val(env, temp_val);
+
+  unprotect(env);
 }
 
 /* Read a string */
@@ -1333,14 +1522,17 @@
   const char symbform[]= "%[a-zA-Z0-9!$%*+./:<=>?@^_~-]%n";
   const char strform[]= "\"%[^\"]\"%n";
   const char intform[]= "%i%n";
+  const char fltform[]= "%f%n";
   const char blankform[]= "%*[ \t]%n";
   const char ebrackform[]= "]%n";
   const char semicform[]= ";%n";
   const char bbrackform[]= "[%n";
 
   int itemp, readlength= -1;
+  int count= -1;
+  float ftemp;
   static int depth= 0;
-  char *match;
+  char *match, *ctemp;
   size_t inlength;
 
   if(env->in_string==NULL) {
@@ -1363,12 +1555,17 @@
   inlength= strlen(env->in_string)+1;
   match= malloc(inlength);
 
-  if(sscanf(env->in_string, blankform, &readlength)!=EOF
+  if(sscanf(env->in_string, blankform, &readlength) != EOF
      && readlength != -1) {
     ; 
-  } else if(sscanf(env->in_string, intform, &itemp, &readlength) != EOF
+  } else if(sscanf(env->in_string, fltform, &ftemp, &readlength) != EOF
 	    && readlength != -1) {
-    push_int(env, itemp);
+    if(sscanf(env->in_string, intform, &itemp, &count) != EOF
+       && count==readlength) {
+      push_int(env, itemp);
+    } else {
+      push_float(env, ftemp);
+    }
   } else if(sscanf(env->in_string, strform, match, &readlength) != EOF
 	    && readlength != -1) {
     push_cstring(env, match);
@@ -1390,7 +1587,7 @@
     free(env->free_string);
     env->in_string = env->free_string = NULL;
   }
-  if ( env->in_string != NULL) {
+  if (env->in_string != NULL) {
     env->in_string += readlength;
   }
 
@@ -1399,3 +1596,498 @@
   if(depth)
     return sx_72656164(env);
 }
+
+extern void beep(environment *env) {
+
+  int freq, dur, period, ticks;
+
+  if((env->head)==NULL || env->head->next==NULL) {
+    printerr("Too Few Arguments");
+    env->err=1;
+    return;
+  }
+
+  if(env->head->item->type!=integer
+     || env->head->next->item->type!=integer) {
+    printerr("Bad Argument Type");
+    env->err=2;
+    return;
+  }
+
+  dur=env->head->item->content.i;
+  toss(env);
+  freq=env->head->item->content.i;
+  toss(env);
+
+  period=1193180/freq;		/* convert freq from Hz to period
+                                   length */
+  ticks=dur*.001193180;		/* convert duration from µseconds to
+				   timer ticks */
+
+/*    ticks=dur/1000; */
+
+  /*  if (ioctl(STDOUT_FILENO, KDMKTONE, (125<<16) + 0x637)==0) */
+  switch (ioctl(STDOUT_FILENO, KDMKTONE, (ticks<<16) | period)){
+  case 0:
+    usleep(dur);
+    return;
+  case -1:
+    perror("beep");
+    env->err=5;
+    return;
+  default:
+    abort();
+  }
+};
+
+/* "wait" */
+extern void sx_77616974(environment *env) {
+
+  int dur;
+
+  if((env->head)==NULL) {
+    printerr("Too Few Arguments");
+    env->err=1;
+    return;
+  }
+
+  if(env->head->item->type!=integer) {
+    printerr("Bad Argument Type");
+    env->err=2;
+    return;
+  }
+
+  dur=env->head->item->content.i;
+  toss(env);
+
+  usleep(dur);
+};
+
+extern void copying(environment *env){
+  printf("GNU GENERAL PUBLIC LICENSE\n\
+		       Version 2, June 1991\n\
+\n\
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.\n\
+     59 Temple Place, Suite 330, Boston, MA  02111-1307  USA\n\
+ Everyone is permitted to copy and distribute verbatim copies\n\
+ of this license document, but changing it is not allowed.\n\
+\n\
+			    Preamble\n\
+\n\
+  The licenses for most software are designed to take away your\n\
+freedom to share and change it.  By contrast, the GNU General Public\n\
+License is intended to guarantee your freedom to share and change free\n\
+software--to make sure the software is free for all its users.  This\n\
+General Public License applies to most of the Free Software\n\
+Foundation's software and to any other program whose authors commit to\n\
+using it.  (Some other Free Software Foundation software is covered by\n\
+the GNU Library General Public License instead.)  You can apply it to\n\
+your programs, too.\n\
+\n\
+  When we speak of free software, we are referring to freedom, not\n\
+price.  Our General Public Licenses are designed to make sure that you\n\
+have the freedom to distribute copies of free software (and charge for\n\
+this service if you wish), that you receive source code or can get it\n\
+if you want it, that you can change the software or use pieces of it\n\
+in new free programs; and that you know you can do these things.\n\
+\n\
+  To protect your rights, we need to make restrictions that forbid\n\
+anyone to deny you these rights or to ask you to surrender the rights.\n\
+These restrictions translate to certain responsibilities for you if you\n\
+distribute copies of the software, or if you modify it.\n\
+\n\
+  For example, if you distribute copies of such a program, whether\n\
+gratis or for a fee, you must give the recipients all the rights that\n\
+you have.  You must make sure that they, too, receive or can get the\n\
+source code.  And you must show them these terms so they know their\n\
+rights.\n\
+\n\
+  We protect your rights with two steps: (1) copyright the software, and\n\
+(2) offer you this license which gives you legal permission to copy,\n\
+distribute and/or modify the software.\n\
+\n\
+  Also, for each author's protection and ours, we want to make certain\n\
+that everyone understands that there is no warranty for this free\n\
+software.  If the software is modified by someone else and passed on, we\n\
+want its recipients to know that what they have is not the original, so\n\
+that any problems introduced by others will not reflect on the original\n\
+authors' reputations.\n\
+\n\
+  Finally, any free program is threatened constantly by software\n\
+patents.  We wish to avoid the danger that redistributors of a free\n\
+program will individually obtain patent licenses, in effect making the\n\
+program proprietary.  To prevent this, we have made it clear that any\n\
+patent must be licensed for everyone's free use or not licensed at all.\n\
+\n\
+  The precise terms and conditions for copying, distribution and\n\
+modification follow.\n\
+\n\
+		    GNU GENERAL PUBLIC LICENSE\n\
+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION\n\
+\n\
+  0. This License applies to any program or other work which contains\n\
+a notice placed by the copyright holder saying it may be distributed\n\
+under the terms of this General Public License.  The \"Program\", below,\n\
+refers to any such program or work, and a \"work based on the Program\"\n\
+means either the Program or any derivative work under copyright law:\n\
+that is to say, a work containing the Program or a portion of it,\n\
+either verbatim or with modifications and/or translated into another\n\
+language.  (Hereinafter, translation is included without limitation in\n\
+the term \"modification\".)  Each licensee is addressed as \"you\".\n\
+\n\
+Activities other than copying, distribution and modification are not\n\
+covered by this License; they are outside its scope.  The act of\n\
+running the Program is not restricted, and the output from the Program\n\
+is covered only if its contents constitute a work based on the\n\
+Program (independent of having been made by running the Program).\n\
+Whether that is true depends on what the Program does.\n\
+\n\
+  1. You may copy and distribute verbatim copies of the Program's\n\
+source code as you receive it, in any medium, provided that you\n\
+conspicuously and appropriately publish on each copy an appropriate\n\
+copyright notice and disclaimer of warranty; keep intact all the\n\
+notices that refer to this License and to the absence of any warranty;\n\
+and give any other recipients of the Program a copy of this License\n\
+along with the Program.\n\
+\n\
+You may charge a fee for the physical act of transferring a copy, and\n\
+you may at your option offer warranty protection in exchange for a fee.\n\
+\n\
+  2. You may modify your copy or copies of the Program or any portion\n\
+of it, thus forming a work based on the Program, and copy and\n\
+distribute such modifications or work under the terms of Section 1\n\
+above, provided that you also meet all of these conditions:\n\
+\n\
+    a) You must cause the modified files to carry prominent notices\n\
+    stating that you changed the files and the date of any change.\n\
+\n\
+    b) You must cause any work that you distribute or publish, that in\n\
+    whole or in part contains or is derived from the Program or any\n\
+    part thereof, to be licensed as a whole at no charge to all third\n\
+    parties under the terms of this License.\n\
+\n\
+    c) If the modified program normally reads commands interactively\n\
+    when run, you must cause it, when started running for such\n\
+    interactive use in the most ordinary way, to print or display an\n\
+    announcement including an appropriate copyright notice and a\n\
+    notice that there is no warranty (or else, saying that you provide\n\
+    a warranty) and that users may redistribute the program under\n\
+    these conditions, and telling the user how to view a copy of this\n\
+    License.  (Exception: if the Program itself is interactive but\n\
+    does not normally print such an announcement, your work based on\n\
+    the Program is not required to print an announcement.)\n\
+\n\
+These requirements apply to the modified work as a whole.  If\n\
+identifiable sections of that work are not derived from the Program,\n\
+and can be reasonably considered independent and separate works in\n\
+themselves, then this License, and its terms, do not apply to those\n\
+sections when you distribute them as separate works.  But when you\n\
+distribute the same sections as part of a whole which is a work based\n\
+on the Program, the distribution of the whole must be on the terms of\n\
+this License, whose permissions for other licensees extend to the\n\
+entire whole, and thus to each and every part regardless of who wrote it.\n\
+\n\
+Thus, it is not the intent of this section to claim rights or contest\n\
+your rights to work written entirely by you; rather, the intent is to\n\
+exercise the right to control the distribution of derivative or\n\
+collective works based on the Program.\n\
+\n\
+In addition, mere aggregation of another work not based on the Program\n\
+with the Program (or with a work based on the Program) on a volume of\n\
+a storage or distribution medium does not bring the other work under\n\
+the scope of this License.\n\
+\n\
+  3. You may copy and distribute the Program (or a work based on it,\n\
+under Section 2) in object code or executable form under the terms of\n\
+Sections 1 and 2 above provided that you also do one of the following:\n\
+\n\
+    a) Accompany it with the complete corresponding machine-readable\n\
+    source code, which must be distributed under the terms of Sections\n\
+    1 and 2 above on a medium customarily used for software interchange; or,\n\
+\n\
+    b) Accompany it with a written offer, valid for at least three\n\
+    years, to give any third party, for a charge no more than your\n\
+    cost of physically performing source distribution, a complete\n\
+    machine-readable copy of the corresponding source code, to be\n\
+    distributed under the terms of Sections 1 and 2 above on a medium\n\
+    customarily used for software interchange; or,\n\
+\n\
+    c) Accompany it with the information you received as to the offer\n\
+    to distribute corresponding source code.  (This alternative is\n\
+    allowed only for noncommercial distribution and only if you\n\
+    received the program in object code or executable form with such\n\
+    an offer, in accord with Subsection b above.)\n\
+\n\
+The source code for a work means the preferred form of the work for\n\
+making modifications to it.  For an executable work, complete source\n\
+code means all the source code for all modules it contains, plus any\n\
+associated interface definition files, plus the scripts used to\n\
+control compilation and installation of the executable.  However, as a\n\
+special exception, the source code distributed need not include\n\
+anything that is normally distributed (in either source or binary\n\
+form) with the major components (compiler, kernel, and so on) of the\n\
+operating system on which the executable runs, unless that component\n\
+itself accompanies the executable.\n\
+\n\
+If distribution of executable or object code is made by offering\n\
+access to copy from a designated place, then offering equivalent\n\
+access to copy the source code from the same place counts as\n\
+distribution of the source code, even though third parties are not\n\
+compelled to copy the source along with the object code.\n\
+\n\
+  4. You may not copy, modify, sublicense, or distribute the Program\n\
+except as expressly provided under this License.  Any attempt\n\
+otherwise to copy, modify, sublicense or distribute the Program is\n\
+void, and will automatically terminate your rights under this License.\n\
+However, parties who have received copies, or rights, from you under\n\
+this License will not have their licenses terminated so long as such\n\
+parties remain in full compliance.\n\
+\n\
+  5. You are not required to accept this License, since you have not\n\
+signed it.  However, nothing else grants you permission to modify or\n\
+distribute the Program or its derivative works.  These actions are\n\
+prohibited by law if you do not accept this License.  Therefore, by\n\
+modifying or distributing the Program (or any work based on the\n\
+Program), you indicate your acceptance of this License to do so, and\n\
+all its terms and conditions for copying, distributing or modifying\n\
+the Program or works based on it.\n\
+\n\
+  6. Each time you redistribute the Program (or any work based on the\n\
+Program), the recipient automatically receives a license from the\n\
+original licensor to copy, distribute or modify the Program subject to\n\
+these terms and conditions.  You may not impose any further\n\
+restrictions on the recipients' exercise of the rights granted herein.\n\
+You are not responsible for enforcing compliance by third parties to\n\
+this License.\n\
+\n\
+  7. If, as a consequence of a court judgment or allegation of patent\n\
+infringement or for any other reason (not limited to patent issues),\n\
+conditions are imposed on you (whether by court order, agreement or\n\
+otherwise) that contradict the conditions of this License, they do not\n\
+excuse you from the conditions of this License.  If you cannot\n\
+distribute so as to satisfy simultaneously your obligations under this\n\
+License and any other pertinent obligations, then as a consequence you\n\
+may not distribute the Program at all.  For example, if a patent\n\
+license would not permit royalty-free redistribution of the Program by\n\
+all those who receive copies directly or indirectly through you, then\n\
+the only way you could satisfy both it and this License would be to\n\
+refrain entirely from distribution of the Program.\n\
+\n\
+If any portion of this section is held invalid or unenforceable under\n\
+any particular circumstance, the balance of the section is intended to\n\
+apply and the section as a whole is intended to apply in other\n\
+circumstances.\n\
+\n\
+It is not the purpose of this section to induce you to infringe any\n\
+patents or other property right claims or to contest validity of any\n\
+such claims; this section has the sole purpose of protecting the\n\
+integrity of the free software distribution system, which is\n\
+implemented by public license practices.  Many people have made\n\
+generous contributions to the wide range of software distributed\n\
+through that system in reliance on consistent application of that\n\
+system; it is up to the author/donor to decide if he or she is willing\n\
+to distribute software through any other system and a licensee cannot\n\
+impose that choice.\n\
+\n\
+This section is intended to make thoroughly clear what is believed to\n\
+be a consequence of the rest of this License.\n\
+\n\
+  8. If the distribution and/or use of the Program is restricted in\n\
+certain countries either by patents or by copyrighted interfaces, the\n\
+original copyright holder who places the Program under this License\n\
+may add an explicit geographical distribution limitation excluding\n\
+those countries, so that distribution is permitted only in or among\n\
+countries not thus excluded.  In such case, this License incorporates\n\
+the limitation as if written in the body of this License.\n\
+\n\
+  9. The Free Software Foundation may publish revised and/or new versions\n\
+of the General Public License from time to time.  Such new versions will\n\
+be similar in spirit to the present version, but may differ in detail to\n\
+address new problems or concerns.\n\
+\n\
+Each version is given a distinguishing version number.  If the Program\n\
+specifies a version number of this License which applies to it and \"any\n\
+later version\", you have the option of following the terms and conditions\n\
+either of that version or of any later version published by the Free\n\
+Software Foundation.  If the Program does not specify a version number of\n\
+this License, you may choose any version ever published by the Free Software\n\
+Foundation.\n\
+\n\
+  10. If you wish to incorporate parts of the Program into other free\n\
+programs whose distribution conditions are different, write to the author\n\
+to ask for permission.  For software which is copyrighted by the Free\n\
+Software Foundation, write to the Free Software Foundation; we sometimes\n\
+make exceptions for this.  Our decision will be guided by the two goals\n\
+of preserving the free status of all derivatives of our free software and\n\
+of promoting the sharing and reuse of software generally.\n");
+}
+
+extern void warranty(environment *env){
+  printf("			    NO WARRANTY\n\
+\n\
+  11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY\n\
+FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN\n\
+OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES\n\
+PROVIDE THE PROGRAM \"AS IS\" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED\n\
+OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF\n\
+MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS\n\
+TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE\n\
+PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,\n\
+REPAIR OR CORRECTION.\n\
+\n\
+  12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING\n\
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR\n\
+REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,\n\
+INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING\n\
+OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED\n\
+TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY\n\
+YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER\n\
+PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE\n\
+POSSIBILITY OF SUCH DAMAGES.\n");
+}
+
+/* "*" */
+extern void sx_2a(environment *env)
+{
+  int a, b;
+  float fa, fb;
+
+  if((env->head)==NULL || env->head->next==NULL) {
+    printerr("Too Few Arguments");
+    env->err=1;
+    return;
+  }
+  
+  if(env->head->item->type==integer
+     && env->head->next->item->type==integer) {
+    a=env->head->item->content.i;
+    toss(env); if(env->err) return;
+    b=env->head->item->content.i;
+    toss(env); if(env->err) return;
+    push_int(env, b*a);
+
+    return;
+  }
+
+  if(env->head->item->type==tfloat
+     && env->head->next->item->type==tfloat) {
+    fa= env->head->item->content.f;
+    toss(env); if(env->err) return;
+    fb= env->head->item->content.f;
+    toss(env); if(env->err) return;
+    push_float(env, fb*fa);
+    
+    return;
+  }
+
+  if(env->head->item->type==tfloat
+     && env->head->next->item->type==integer) {
+    fa= env->head->item->content.f;
+    toss(env); if(env->err) return;
+    b= env->head->item->content.i;
+    toss(env); if(env->err) return;
+    push_float(env, b*fa);
+    
+    return;
+  }
+
+  if(env->head->item->type==integer
+     && env->head->next->item->type==tfloat) {
+    a= env->head->item->content.i;
+    toss(env); if(env->err) return;
+    fb= env->head->item->content.f;
+    toss(env); if(env->err) return;
+    push_float(env, fb*a);
+
+    return;
+  }
+
+  printerr("Bad Argument Type");
+  env->err=2;
+}
+
+/* "/" */
+extern void sx_2f(environment *env)
+{
+  int a, b;
+  float fa, fb;
+
+  if((env->head)==NULL || env->head->next==NULL) {
+    printerr("Too Few Arguments");
+    env->err=1;
+    return;
+  }
+  
+  if(env->head->item->type==integer
+     && env->head->next->item->type==integer) {
+    a=env->head->item->content.i;
+    toss(env); if(env->err) return;
+    b=env->head->item->content.i;
+    toss(env); if(env->err) return;
+    push_float(env, b/a);
+
+    return;
+  }
+
+  if(env->head->item->type==tfloat
+     && env->head->next->item->type==tfloat) {
+    fa= env->head->item->content.f;
+    toss(env); if(env->err) return;
+    fb= env->head->item->content.f;
+    toss(env); if(env->err) return;
+    push_float(env, fb/fa);
+    
+    return;
+  }
+
+  if(env->head->item->type==tfloat
+     && env->head->next->item->type==integer) {
+    fa= env->head->item->content.f;
+    toss(env); if(env->err) return;
+    b= env->head->item->content.i;
+    toss(env); if(env->err) return;
+    push_float(env, b/fa);
+    
+    return;
+  }
+
+  if(env->head->item->type==integer
+     && env->head->next->item->type==tfloat) {
+    a= env->head->item->content.i;
+    toss(env); if(env->err) return;
+    fb= env->head->item->content.f;
+    toss(env); if(env->err) return;
+    push_float(env, fb/a);
+
+    return;
+  }
+
+  printerr("Bad Argument Type");
+  env->err=2;
+}
+
+/* "mod" */
+extern void mod(environment *env)
+{
+  int a, b;
+
+  if((env->head)==NULL || env->head->next==NULL) {
+    printerr("Too Few Arguments");
+    env->err=1;
+    return;
+  }
+  
+  if(env->head->item->type==integer
+     && env->head->next->item->type==integer) {
+    a= env->head->item->content.i;
+    toss(env); if(env->err) return;
+    b= env->head->item->content.i;
+    toss(env); if(env->err) return;
+    push_int(env, b%a);
+
+    return;
+  }
+
+  printerr("Bad Argument Type");
+  env->err=2;
+}