diff --git a/c/external.c b/c/external.c
index 67c4053..d6cf637 100644
--- a/c/external.c
+++ b/c/external.c
@@ -762,7 +762,7 @@ s48_enter_unsigned_integer(unsigned long value)
 
     return s48_call_scheme(S48_SHARED_BINDING_REF(long_to_bignum_binding),
 			   3,
-			   S48_FALSE,   // this is ok
+			   S48_FALSE,   /* this is ok */
 			   S48_UNSAFE_ENTER_FIXNUM(value >> 16),
 			   S48_UNSAFE_ENTER_FIXNUM(value & 0xFFFF));
   }
@@ -1089,14 +1089,14 @@ s48_length(s48_value list)
   return S48_UNSAFE_ENTER_FIXNUM(i);
 }
 
-////////////////////////////////////////////////////////////////////////////////
-// 
-//  Support for libscsh.a: add external initializers without the Makefile
-//
-////////////////////////////////////////////////////////////////////////////////
+/*
+** 
+**  Support for libscsh.a: add external initializers without the Makefile
+**
+*/
 
 struct simple_list{
-  void (*init)();          // pointer to init-function
+  void (*init)();          /* pointer to init-function */
   struct  simple_list* next;
 };
 
diff --git a/c/init.c b/c/init.c
index 8a4f185..4b63075 100644
--- a/c/init.c
+++ b/c/init.c
@@ -10,7 +10,7 @@
 extern void	s48_sysdep_init(void);
 extern void	s48_initialize_external_modules(void);
 
-// JMG: s48_object_file is obsolete according to s48 manual
+/* JMG: s48_object_file is obsolete according to s48 manual */
 char *s48_object_file;   /* specified via a command line argument */
 
 char *s48_reloc_file;    /* dynamic loading will set this */
diff --git a/c/main.c b/c/main.c
index 2c44c4a..6d4c0e0 100644
--- a/c/main.c
+++ b/c/main.c
@@ -46,7 +46,7 @@ int
 main(argc, argv)
      int argc; char **argv;
 {
-  char **argp; //JMG
+  char **argp; /* JMG */
   char *image_name = DEFAULT_IMAGE_NAME;
   long heap_size = DEFAULT_HEAP_SIZE;    /* in numbers of cells */
   long stack_size = DEFAULT_STACK_SIZE;  /* in numbers of cells */
diff --git a/c/unix/event.c b/c/unix/event.c
index fb46fd6..63a8fa0 100644
--- a/c/unix/event.c
+++ b/c/unix/event.c
@@ -26,7 +26,7 @@ static void	when_keyboard_interrupt();
 static void	when_alarm_interrupt();
 static void     when_sigpipe_interrupt();
 
-//JMG:
+/* JMG:*/
 static void     when_scsh_interrupt();
 
 
@@ -46,7 +46,7 @@ s48_sysdep_init(void)
     exit(1);
   }
 
-  //JMG: for scsh
+  /* JMG: for scsh */
   s48_setcatcher(SIGCHLD,   when_scsh_interrupt);
   s48_setcatcher(SIGCONT,   when_scsh_interrupt);
   s48_setcatcher(SIGHUP,    when_scsh_interrupt);
@@ -101,9 +101,9 @@ s48_setcatcher(int signum, void (*catcher)(int))
     fprintf(stderr, "Failed to get sigaction for signal %d\n", signum);
     exit(1);
   }
-  //  JMG: what's the point of not setting the handler in this case?
-  //  if (sa.sa_handler == SIG_IGN)
-  //  return (TRUE);
+  /*  JMG: what's the point of not setting the handler in this case?
+      if (sa.sa_handler == SIG_IGN)
+      return (TRUE);*/
   sa.sa_handler = catcher;
   sigemptyset(&sa.sa_mask);
   sa.sa_flags = 0;
@@ -333,7 +333,7 @@ s48_get_next_event(long *ready_fd, long *status)
     /* fprintf(stderr, "[alarm]\n"); */
     return (ALARM_EVENT);
   }
-  //JMG: scsh should handle this
+  /* JMG: scsh should handle this */
   if (s48_os_signal_pending())
     return (OS_SIGNAL_EVENT);
     
@@ -643,7 +643,7 @@ queue_ready_ports(bool wait, long seconds, long ticks)
 }
 
 
-//JMG: for scsh
+/* JMG: for scsh */
 static long interrupt_count[32];
 
 static void when_scsh_interrupt(int signo)
diff --git a/cig/cig.scm b/cig/cig.scm
index 466785c..5d46356 100644
--- a/cig/cig.scm
+++ b/cig/cig.scm
@@ -186,12 +186,12 @@
 ;;; Emit C code to copy a C string into its carrier.
 (define (str-and-len->carrier carrier str)
   (format #f
-	  "SetAlienVal(S48_CAR(~a),(long) ~a); S48_SET_CDR(~a,strlen_or_false(~a));//str-and-len"
+	  "SetAlienVal(S48_CAR(~a),(long) ~a); S48_SET_CDR(~a,strlen_or_false(~a));"
 	  carrier str carrier str))
 
 ;;; Carrier and assignment-generator for alien values:
 (define (simple-assign carrier val)
-  (format #f "SetAlienVal(~a,(long) ~a);//simple-assign" carrier val)) ;;JMG: untested
+  (format #f "SetAlienVal(~a,(long) ~a);" carrier val)) ;;JMG: untested
 
 ;;; Note: When MAKE-CARRIER and S-CVTR fields are taken from this table,
 ;;; they are symbols that are syntactically closed in the macro expander's
diff --git a/cig/libcig.h b/cig/libcig.h
index b0a30e7..9f5bb45 100644
--- a/cig/libcig.h
+++ b/cig/libcig.h
@@ -5,20 +5,20 @@
 #define StobData(x) (S48_ADDRESS_AFTER_HEADER(x, s48_value))
 
 #define IsChar(x) ((((long) x) & 0xff) == S48_CHAR) 
-//JMG: untested !!
+/* JMG: untested !! */
 
 #define StrByte(x, i)  ((i) + S48_ADDRESS_AFTER_HEADER((x), char))
 #define cig_string_body(x) (S48_ADDRESS_AFTER_HEADER((x), char))
 
 #define AlienVal(x) (S48_STOB_REF((x),0))
-//JMG: no () around this, because it's a do..while(0)
+/* JMG: no () around this, because it's a do..while(0) */
 #define SetAlienVal(x, v) S48_STOB_SET((x), 0, (v))
 
-//  JMG: some hacks to leave to old sources untouched
+/*  JMG: some hacks to leave to old sources untouched */
 #define ENTER_BOOLEAN(x) (x ? S48_TRUE : S48_FALSE)
 #define EXTRACT_BOOLEAN(x) ((x==S48_TRUE) ? 1 : 0)
-//#define ENTER_FIXNUM(x) (s48_enter_fixnum(x))
-//#define SCHFALSE S48_FALSE
+/* #define ENTER_FIXNUM(x) (s48_enter_fixnum(x)) */
+/* #define SCHFALSE S48_FALSE */
 
 extern char *scheme2c_strcpy(s48_value sstr);
 
diff --git a/cig/libcig1.c b/cig/libcig1.c
index c8a22c5..f312500 100644
--- a/cig/libcig1.c
+++ b/cig/libcig1.c
@@ -127,7 +127,7 @@ void set_strvec_carriers(s48_value svec, char const * const * cvec)
     char const * const * cv = cvec;
     int i = 0;
        
-    // JMG: now using normal array access, instead of pointer++ on a s48_value
+    /* JMG: now using normal array access, instead of pointer++ on a s48_value */
     for(; svec_len > 0; i++, cv++, svec_len-- ) {
       s48_value carrier, alien;
       int strl;
diff --git a/scsh/network1.c b/scsh/network1.c
index 4662857..3eaddb5 100644
--- a/scsh/network1.c
+++ b/scsh/network1.c
@@ -169,7 +169,7 @@ s48_value scheme_accept(s48_value sockfd_tagged, s48_value family)
 	  {
 	    if ((errno != EWOULDBLOCK) && (errno != EINTR) && (errno != EAGAIN))
 	      s48_raise_os_error_2(errno, sockfd_tagged, family);
-	    if (! s48_add_pending_fd(sockfd, 1))// 1 for is_input
+	    if (! s48_add_pending_fd(sockfd, 1))/* 1 for is_input */
 	      s48_raise_out_of_memory_error();
 	    return S48_FALSE;
 	  }
@@ -191,7 +191,7 @@ s48_value scheme_accept(s48_value sockfd_tagged, s48_value family)
 	  {
 	    if ((errno != EWOULDBLOCK) && (errno != EINTR) && (errno != EAGAIN))
 	      s48_raise_os_error_2(errno, sockfd_tagged, family);
-	    if (! s48_add_pending_fd(sockfd, 1))// 1 for is_input
+	    if (! s48_add_pending_fd(sockfd, 1))/* 1 for is_input */
 	      s48_raise_out_of_memory_error();
 	    return S48_FALSE;
 	  }
@@ -316,7 +316,7 @@ recv_substring(s48_value scm_sockfd, s48_value flags, s48_value buf,
   
   if ((errno != EWOULDBLOCK) && (errno != EINTR) && (errno != EAGAIN))
     s48_raise_os_error_5(errno, scm_sockfd, flags, buf, scm_start, scm_end);
-  if (! s48_add_pending_fd(sockfd, 1))// 1 for is_input
+  if (! s48_add_pending_fd(sockfd, 1))/* 1 for is_input */
     s48_raise_out_of_memory_error();
 	return S48_FALSE;
 }
@@ -400,7 +400,7 @@ s48_value send_substring(s48_value scm_sockfd,
 			 scm_family, 
 			 scheme_name);
   
-  if (! s48_add_pending_fd(s, 0))// 0 for is_input
+  if (! s48_add_pending_fd(s, 0))/* 0 for is_input */
     s48_raise_out_of_memory_error();
   
   return S48_FALSE;
@@ -647,7 +647,7 @@ s48_value netent2net_info(struct netent *net)
 s48_value scheme_net_address2net_info(s48_value net_addr)
 {
   struct netent *net;
-  // expects host byte order :
+  /* expects host byte order */
   net=getnetbyaddr(s48_extract_unsigned_integer (net_addr),AF_INET); 
   
   return netent2net_info (net);
diff --git a/scsh/scsh_aux.h b/scsh/scsh_aux.h
index 774c20c..1af5425 100644
--- a/scsh/scsh_aux.h
+++ b/scsh/scsh_aux.h
@@ -16,7 +16,7 @@
 */
 #define scshint_alarm (0)		/* S48 Unix SIGALRM signal */
 #define scshint_keyboard (1)		/* S48 Unix SIGINT signal */
-// left out post-gc and i/o-completion
+/* left out post-gc and i/o-completion */
 #define scshint_chld (4)		/* Interrupts from here down are    */
 #define scshint_cont (5)		/* Unix signals. The last ten are   */
 #define scshint_hup (6)			/* non-Posix, hence not necessarily */
diff --git a/scsh/select1.c b/scsh/select1.c
index 7c29f95..984af8e 100644
--- a/scsh/select1.c
+++ b/scsh/select1.c
@@ -140,7 +140,7 @@ static int copyback_fdvec(s48_value portvec, fd_set *fdset)
     for( i = -1; ++i < vlen; ) {
 	s48_value elt = S48_VECTOR_REF(portvec, i);
 	int fd = s48_extract_fixnum((S48_FIXNUM_P(elt)) ? elt : (1 / 0));
-	//JMG *PortFd(elt));
+	/* JMG *PortFd(elt));*/
 	if( FD_ISSET(fd,fdset) ) {
 	    FD_CLR(fd,fdset);	/* In case luser put elt in multiple times. */
 	    S48_VECTOR_SET(portvec, j, elt);
@@ -163,7 +163,7 @@ static int clobber_inactives(s48_value portvec, fd_set *fdset)
     while( --i >= 0 ) {
 	s48_value elt = S48_VECTOR_REF(portvec, i);
 	if( elt != S48_FALSE ) {
-	  int fd = s48_extract_fixnum((S48_FIXNUM_P(elt)) ? elt : (1/0)); //JMG *PortFd(elt));
+	  int fd = s48_extract_fixnum((S48_FIXNUM_P(elt)) ? elt : (1/0)); /* JMG *PortFd(elt));*/
 	    if( FD_ISSET(fd,fdset) ) {
 		FD_CLR(fd,fdset); /* In case luser put elt in multiple times. */
 		++count;
diff --git a/scsh/syscalls1.c b/scsh/syscalls1.c
index be40c8d..df6b08d 100644
--- a/scsh/syscalls1.c
+++ b/scsh/syscalls1.c
@@ -116,8 +116,8 @@ s48_value scheme_exec(s48_value prog, s48_value argv, s48_value env)
     Free(unix_env);
   }
   Free(unix_argv);
-  return s48_enter_fixnum(e); // Don't raise an exception since
-                              // we're maybe just testing the path
+  return s48_enter_fixnum(e); /* Don't raise an exception since
+				 we're maybe just testing the path */
 }
 
 s48_value scsh_exit(s48_value status)
@@ -651,7 +651,7 @@ s48_value get_groups()
     if (veclen > 20) Free(gp);
     s48_raise_os_error(errno);
   }
-  else if (retval != veclen){     // paranoia...
+  else if (retval != veclen){     /* paranoia... */
     get_groups();
   }
   else{
@@ -907,7 +907,7 @@ s48_value scm_crypt(s48_value key, s48_value salt)
   char * ret = crypt (s48_extract_string (key), 
 		      s48_extract_string(salt));
 
-  // FreeBSD does this on error:
+  /* FreeBSD does this on error:*/
   if (ret == NULL) return s48_enter_string("");
 
   return s48_enter_string (ret);
diff --git a/scsh/time1.c b/scsh/time1.c
index fd6fd73..ee5acd7 100644
--- a/scsh/time1.c
+++ b/scsh/time1.c
@@ -46,7 +46,7 @@
 #include "cstuff.h"
 #include "time1.h"	/* Make sure the .h interface agrees with the code. */
 
-#include <stdio.h>     // JMG debug
+#include <stdio.h>     /* JMG debug */
 
 extern char **environ;
 
@@ -76,12 +76,12 @@ static char **make_newenv(s48_value zone, char *newenv[2])
     
     char * extracted_zone = s48_extract_string(zone);
     
-    // s48_value temp;
+    /* s48_value temp; */
     if( !tz ) return NULL;
     strcpy(tz, "TZ=");
 
-    //    temp = S48_STRING_REF(zone,0); //JMG
-    // strncpy(tz+3, &temp, zonelen);
+    /*    temp = S48_STRING_REF(zone,0);*/ /* JMG */
+    /* strncpy(tz+3, &temp, zonelen);*/
     strncpy(tz+3, extracted_zone, zonelen);
     tz[zonelen+3] = '\0';
     newenv[0] = tz;
@@ -113,7 +113,7 @@ s48_value scheme_time()
     return s48_enter_integer (t);
 }
 
-// should be part of the FFI interface
+/* should be part of the FFI interface */
 s48_value s48_list_11 (s48_value e1, s48_value e2, s48_value e3, 
 		       s48_value e4, s48_value e5, s48_value e6, 
 		       s48_value e7, s48_value e8, s48_value e9, 
@@ -255,7 +255,7 @@ s48_value date2time(s48_value sec, s48_value min, s48_value hour,
 	t = mktime(&d);
 	/* t == -1 => you probably have an error. */
 	if ((t == -1) && (errno != 0))
-	  // Sorry, we only have a version with 5 arguments...
+	  /* Sorry, we only have a version with 5 arguments..*/
 	  s48_raise_os_error_5 (errno, sec, min, hour, mday, month);
 	t -= s48_extract_fixnum(tz_secs);
 	environ = oldenv;
diff --git a/scsh/tty1.c b/scsh/tty1.c
index 50e27df..58559d8 100644
--- a/scsh/tty1.c
+++ b/scsh/tty1.c
@@ -29,7 +29,7 @@
 #include "tty1.h"	/* Make sure the .h interface agrees with the code. */
 
 /*****************************************************************************/
-// should be part of the FFI interface
+/* should be part of the FFI interface */
 s48_value s48_list_6 (s48_value e1, s48_value e2, s48_value e3, 
 		      s48_value e4, s48_value e5, s48_value e6)
 {
@@ -63,14 +63,14 @@ s48_value scheme_tcgetattr(s48_value sch_fd, s48_value sch_control_chars)
 		s48_enter_integer (cfgetospeed(&t)));
 }
 
-// The Scheme caller of this is commented out...
+/* The Scheme caller of this is commented out...*/
 int scheme_tcgetattrB(int fd, char *control_chars, s48_value scmvec)
 {
   struct termios t;
   int result = tcgetattr(fd, &t);
   S48_DECLARE_GC_PROTECT(1);
   S48_GC_PROTECT_1(scmvec);
-  // JMG  int *ivec = ADDRESS_AFTER_HEADER(scmvec, int);
+  /* JMG  int *ivec = ADDRESS_AFTER_HEADER(scmvec, int);*/
   
   if (result != -1) {
       memcpy(control_chars, t.c_cc, NCCS);