diff --git a/src/c/file.d b/src/c/file.d
index e13d70a25..915f0a95d 100755
--- a/src/c/file.d
+++ b/src/c/file.d
@@ -4740,12 +4740,12 @@ writestr_stream(const char *s, cl_object strm)
     ecl_char_set(buffer, i++, (ecl_character) *s++);
     if (i >= size) {
       si_fill_pointer_set(buffer, ecl_make_fixnum(size));
-      cl_write_string(2, buffer, strm);
+      si_do_write_sequence(buffer, strm, ecl_make_fixnum(0), ECL_NIL);
       i = 0;
     }
   }
   si_fill_pointer_set(buffer, ecl_make_fixnum(i));
-  cl_write_string(2, buffer, strm);
+  si_do_write_sequence(buffer, strm, ecl_make_fixnum(0), ECL_NIL);
   si_put_buffer_string(buffer);
 }
 
diff --git a/src/c/printer/print_unreadable.d b/src/c/printer/print_unreadable.d
index 7f244baf6..d2a75d859 100644
--- a/src/c/printer/print_unreadable.d
+++ b/src/c/printer/print_unreadable.d
@@ -43,13 +43,13 @@ _ecl_write_addr(void *x, cl_object stream)
       }
       if (buffer_ndx >= buffer_size) {
         si_fill_pointer_set(buffer, ecl_make_fixnum(buffer_size));
-        cl_write_string(2, buffer, stream);
+        si_do_write_sequence(buffer, stream, ecl_make_fixnum(0), ECL_NIL);
         buffer_ndx = 0;
       }
     }
   }
   si_fill_pointer_set(buffer, ecl_make_fixnum(buffer_ndx));
-  cl_write_string(2, buffer, stream);
+  si_do_write_sequence(buffer, stream, ecl_make_fixnum(0), ECL_NIL);
   si_put_buffer_string(buffer);
 }
 
diff --git a/src/c/printer/write_array.d b/src/c/printer/write_array.d
index 164c777b7..2fb17d766 100644
--- a/src/c/printer/write_array.d
+++ b/src/c/printer/write_array.d
@@ -149,19 +149,19 @@ void
 _ecl_write_string(cl_object x, cl_object stream)
 {
   if (!ecl_print_escape() && !ecl_print_readably()) {
-    cl_write_string(2, x, stream);
+    si_do_write_sequence(x, stream, ecl_make_fixnum(0), ECL_NIL);
   } else {
     cl_index ndx, ndx_start;
     ecl_write_char('"', stream);
     for (ndx = ndx_start = 0;  ndx < x->string.fillp;  ndx++) {
       ecl_character c = x->string.self[ndx];
       if (c == '"' || c == '\\') {
-        cl_write_string(6, x, stream, @':start', ecl_make_fixnum(ndx_start), @':end', ecl_make_fixnum(ndx));
+        si_do_write_sequence(x, stream, ecl_make_fixnum(ndx_start), ecl_make_fixnum(ndx));
         ecl_write_char('\\', stream);
         ndx_start = ndx;
       }
     }
-    cl_write_string(4, x, stream, @':start', ecl_make_fixnum(ndx_start));
+    si_do_write_sequence(x, stream, ecl_make_fixnum(ndx_start), ECL_NIL);
     ecl_write_char('"', stream);
   }
 }
@@ -171,19 +171,19 @@ void
 _ecl_write_base_string(cl_object x, cl_object stream)
 {
   if (!ecl_print_escape() && !ecl_print_readably()) {
-    cl_write_string(2, x, stream);
+    si_do_write_sequence(x, stream, ecl_make_fixnum(0), ECL_NIL);
   } else {
     cl_index ndx, ndx_start;
     ecl_write_char('"', stream);
     for (ndx = ndx_start = 0;  ndx < x->base_string.fillp;  ndx++) {
       ecl_character c = x->base_string.self[ndx];
       if (c == '"' || c == '\\') {
-        cl_write_string(6, x, stream, @':start', ecl_make_fixnum(ndx_start), @':end', ecl_make_fixnum(ndx));
+        si_do_write_sequence(x, stream, ecl_make_fixnum(ndx_start), ecl_make_fixnum(ndx));
         ecl_write_char('\\', stream);
         ndx_start = ndx;
       }
     }
-    cl_write_string(4, x, stream, @':start', ecl_make_fixnum(ndx_start));
+    si_do_write_sequence(x, stream, ecl_make_fixnum(ndx_start), ECL_NIL);
     ecl_write_char('"', stream);
   }
 }
diff --git a/src/c/printer/write_symbol.d b/src/c/printer/write_symbol.d
index 0e34a6ce5..1e1d4e2b9 100644
--- a/src/c/printer/write_symbol.d
+++ b/src/c/printer/write_symbol.d
@@ -106,7 +106,7 @@ needs_to_be_escaped(cl_object s, cl_object readtable, cl_object print_case)
   ecl_char_set(buffer, buffer_ndx++, c);                              \
   if (buffer_ndx >= buffer_size) {                                    \
     si_fill_pointer_set(buffer, ecl_make_fixnum(buffer_size));        \
-    cl_write_string(2, buffer, stream);                               \
+    si_do_write_sequence(buffer, stream, ecl_make_fixnum(0), ECL_NIL);\
     buffer_ndx = 0;                                                   \
   }
 
@@ -160,7 +160,7 @@ write_symbol_string(cl_object s, int action, cl_object print_case,
   if (escape)
     buffer_write_char('|', buffer, stream, buffer_ndx, buffer_size);
   si_fill_pointer_set(buffer, ecl_make_fixnum(buffer_ndx));
-  cl_write_string(2, buffer, stream);
+  si_do_write_sequence(buffer, stream, ecl_make_fixnum(0), ECL_NIL);
   si_put_buffer_string(buffer);
 }