diff --git a/src/eccodes.c b/src/eccodes.c
index ffb3d02bb..6b7394b3f 100644
--- a/src/eccodes.c
+++ b/src/eccodes.c
@@ -65,7 +65,7 @@ void codes_check(const char* call,const char*  file,int line,int e,const char* m
 
 /* Fieldsets */
 /******************************************************************************/
-grib_fieldset *codes_fieldset_new_from_files(grib_context *c, char *filenames[], int nfiles, char **keys, int nkeys, char *where_string, char *order_by_string, int *err)
+grib_fieldset *codes_fieldset_new_from_files(grib_context *c, char *filenames[], int nfiles, char **keys, int nkeys, const char *where_string, const char *order_by_string, int *err)
 {
     return grib_fieldset_new_from_files(c, filenames, nfiles, keys, nkeys, where_string, order_by_string, err);
 }
diff --git a/src/eccodes.h b/src/eccodes.h
index d7b122330..347b58207 100644
--- a/src/eccodes.h
+++ b/src/eccodes.h
@@ -179,7 +179,7 @@ typedef struct grib_util_packing_spec codes_util_packing_spec;
 typedef struct grib_util_grid_spec    codes_util_grid_spec;
 
 
-codes_fieldset *codes_fieldset_new_from_files(codes_context *c, char *filenames[], int nfiles, char **keys, int nkeys, char *where_string, char *order_by_string, int *err);
+codes_fieldset *codes_fieldset_new_from_files(codes_context *c, char *filenames[], int nfiles, char **keys, int nkeys, const char *where_string, const char *order_by_string, int *err);
 
 void codes_fieldset_delete(codes_fieldset* set);
 void codes_fieldset_rewind(codes_fieldset* set);
diff --git a/src/grib_api.h b/src/grib_api.h
index 14be8e77d..fc3e4e15a 100644
--- a/src/grib_api.h
+++ b/src/grib_api.h
@@ -225,7 +225,7 @@ typedef struct grib_viarray grib_viarray;
 typedef struct bufr_descriptor bufr_descriptor;
 typedef struct bufr_descriptors_array bufr_descriptors_array;
 
-grib_fieldset *grib_fieldset_new_from_files(grib_context *c, char *filenames[], int nfiles, char **keys, int nkeys, char *where_string, char *order_by_string, int *err);
+grib_fieldset *grib_fieldset_new_from_files(grib_context *c, char *filenames[], int nfiles, char **keys, int nkeys, const char *where_string, const char *order_by_string, int *err);
 void grib_fieldset_delete(grib_fieldset* set);
 void grib_fieldset_rewind(grib_fieldset* set);
 int grib_fieldset_apply_order_by(grib_fieldset* set,const char* order_by_string);
@@ -801,7 +801,7 @@ int grib_get_double_elements(grib_handle* h, const char* key, int* i, long size,
 * @param length      : the address of a size_t that contains allocated length of the string on input, and that contains the actual length of the string on output
 * @return            0 if OK, integer value on error
 */
-int grib_get_string       (grib_handle* h, const char* key, char*   mesg,             size_t *length);
+int grib_get_string(grib_handle* h, const char* key, char* mesg, size_t *length);
 
 int grib_get_string_array(grib_handle* h, const char* name, char** val, size_t *length);
 
diff --git a/src/grib_api_prototypes.h b/src/grib_api_prototypes.h
index f544060ab..b8a06b9f7 100644
--- a/src/grib_api_prototypes.h
+++ b/src/grib_api_prototypes.h
@@ -990,7 +990,7 @@ long grib_date_to_julian(long ddate);
 /* grib_fieldset.c */
 int grib_fieldset_new_column(grib_fieldset *set, int id, char *key, int type);
 int grib_fieldset_column_copy_from_handle(grib_handle *h, grib_fieldset *set, int i);
-grib_fieldset *grib_fieldset_new_from_files(grib_context *c, char *filenames[], int nfiles, char **keys, int nkeys, char *where_string, char *order_by_string, int *err);
+grib_fieldset *grib_fieldset_new_from_files(grib_context *c, char *filenames[], int nfiles, char **keys, int nkeys, const char *where_string, const char *order_by_string, int *err);
 int grib_fieldset_apply_where(grib_fieldset *set, const char *where_string);
 int grib_fieldset_apply_order_by(grib_fieldset *set, const char *order_by_string);
 void grib_fieldset_delete_order_by(grib_context *c, grib_order_by *order_by);
diff --git a/src/grib_fieldset.c b/src/grib_fieldset.c
index 32090cda6..59c776999 100644
--- a/src/grib_fieldset.c
+++ b/src/grib_fieldset.c
@@ -33,7 +33,7 @@ static grib_fieldset* grib_fieldset_create_from_order_by(grib_context* c,grib_or
         int* err);
 static int grib_fieldset_resize(grib_fieldset* set,size_t newsize);
 static void grib_trim(char** x);
-static grib_order_by* grib_fieldset_new_order_by(grib_context* c,char* z);
+static grib_order_by* grib_fieldset_new_order_by(grib_context* c, const char* z);
 static int grib_fieldset_compare(grib_fieldset* set,int* i,int* j);
 static void grib_fieldset_sort(grib_fieldset* set, int beg, int theEnd);
 static int grib_fieldset_columns_resize(grib_fieldset* set,size_t newsize);
@@ -238,8 +238,8 @@ int grib_fieldset_column_copy_from_handle(grib_handle* h,grib_fieldset* set,int
 
 /* --------------- grib_fieldset functions ------------------*/
 grib_fieldset* grib_fieldset_new_from_files(grib_context* c,char* filenames[],
-        int nfiles, char** keys,int nkeys,
-        char* where_string,char* order_by_string,int* err)
+        int nfiles, char** keys, int nkeys,
+        const char* where_string, const char* order_by_string, int* err)
 {
     int i=0;
     int ret=GRIB_SUCCESS;
@@ -403,7 +403,7 @@ int grib_fieldset_apply_order_by(grib_fieldset* set,const char* order_by_string)
         set->order_by=0;
     }
 
-    ob=grib_fieldset_new_order_by(set->context,(char*)order_by_string);
+    ob=grib_fieldset_new_order_by(set->context, order_by_string);
     if ((err=grib_fieldset_set_order_by(set,ob)) != GRIB_SUCCESS)
         return err;
 
@@ -509,7 +509,7 @@ void grib_fieldset_delete_order_by(grib_context* c,grib_order_by* order_by)
     return;
 }
 
-static grib_order_by* grib_fieldset_new_order_by(grib_context* c,char* obstr)
+static grib_order_by* grib_fieldset_new_order_by(grib_context* c, const char* obstr)
 {
     char *t1=0,*t2=0,*p=0;
     int id=0;
diff --git a/src/grib_value.c b/src/grib_value.c
index ab69baf82..07d3837be 100644
--- a/src/grib_value.c
+++ b/src/grib_value.c
@@ -155,7 +155,7 @@ int grib_copy_namespace(grib_handle* dest, const char* name, grib_handle* src)
 
     if (!dest || !src) return GRIB_NULL_HANDLE;
 
-    iter=grib_keys_iterator_new(src,0,(char*)name);
+    iter=grib_keys_iterator_new(src,0,name);
 
     if (!iter) {
         grib_context_log(src->context,GRIB_LOG_ERROR,"grib_copy_namespace: unable to get iterator for %s",name );
@@ -1383,7 +1383,7 @@ static int grib_get_key_value(grib_handle* h,grib_key_value_list* kv)
         kv->error=err;
         break;
     case GRIB_NAMESPACE:
-        iter=grib_keys_iterator_new(h,0,(char*)kv->name);
+        iter=grib_keys_iterator_new(h,0,kv->name);
         list=(grib_key_value_list*)grib_context_malloc_clear(h->context,sizeof(grib_key_value_list));
         kv->namespace_value=list;
         while(grib_keys_iterator_next(iter))
diff --git a/tools/bufr_compare.c b/tools/bufr_compare.c
index cfa556e38..6837abcfd 100644
--- a/tools/bufr_compare.c
+++ b/tools/bufr_compare.c
@@ -1181,7 +1181,7 @@ static int compare_handles(grib_handle* handle1, grib_handle* handle2, grib_runt
         for (i=0; i< options->compare_count; i++) {
             if (blacklisted((char*)options->compare[i].name)) continue;
             if (options->compare[i].type == GRIB_NAMESPACE) {
-                iter=grib_keys_iterator_new(handle1,0,(char*)options->compare[i].name);
+                iter=grib_keys_iterator_new(handle1,0,options->compare[i].name);
                 if (!iter) {
                     grib_context_log(handle1->context, GRIB_LOG_ERROR, "unable to get iterator");
                     exit(1);
@@ -1241,7 +1241,7 @@ static int compare_handles(grib_handle* handle1, grib_handle* handle2, grib_runt
             for (i=0; i< options->compare_count; i++) {
                 if (blacklisted(name)) continue;
                 if (options->compare[i].type == GRIB_NAMESPACE) {
-                    iter=grib_keys_iterator_new(handle1,0,(char*)options->compare[i].name);
+                    iter=grib_keys_iterator_new(handle1,0,options->compare[i].name);
                     if (!iter) {
                         grib_context_log(handle1->context, GRIB_LOG_ERROR,
                                 "ERROR: unable to get keys iterator for %s",options->compare[i].name);
diff --git a/tools/grib_tools.c b/tools/grib_tools.c
index 73aa36c09..32fb5404a 100644
--- a/tools/grib_tools.c
+++ b/tools/grib_tools.c
@@ -673,7 +673,7 @@ static void grib_tools_set_print_keys(grib_runtime_options* options, grib_handle
     }
 
     if (ns) {
-        kiter=grib_keys_iterator_new(h,0,(char*)ns);
+        kiter=grib_keys_iterator_new(h,0,ns);
         if (!kiter) {
             fprintf(dump_file,"ERROR: Unable to create keys iterator\n");
             exit(1);
diff --git a/tools/gts_compare.c b/tools/gts_compare.c
index 57c17a52c..ee967abff 100644
--- a/tools/gts_compare.c
+++ b/tools/gts_compare.c
@@ -841,7 +841,7 @@ static int compare_handles(grib_handle* h1,grib_handle* h2,grib_runtime_options*
         for (i=0; i< options->compare_count; i++) {
             if (blacklisted((char*)options->compare[i].name)) continue;
             if (options->compare[i].type == GRIB_NAMESPACE) {
-                iter=grib_keys_iterator_new(h1,0,(char*)options->compare[i].name);
+                iter=grib_keys_iterator_new(h1,0,options->compare[i].name);
                 if (!iter) {
                     printf("ERROR: unable to get iterator\n");
                     exit(1);
@@ -901,7 +901,7 @@ static int compare_handles(grib_handle* h1,grib_handle* h2,grib_runtime_options*
             for (i=0; i< options->compare_count; i++) {
                 if (blacklisted(name)) continue;
                 if (options->compare[i].type == GRIB_NAMESPACE) {
-                    iter=grib_keys_iterator_new(h1,0,(char*)options->compare[i].name);
+                    iter=grib_keys_iterator_new(h1,0,options->compare[i].name);
                     if (!iter) {
                         printf("ERROR: unable to get iterator for %s\n",options->compare[i].name );
                         exit(1);
diff --git a/tools/metar_compare.c b/tools/metar_compare.c
index fd16991cd..f920e5625 100644
--- a/tools/metar_compare.c
+++ b/tools/metar_compare.c
@@ -1067,7 +1067,7 @@ static int compare_handles(grib_handle* h1,grib_handle* h2,grib_runtime_options*
         for (i=0; i< options->compare_count; i++) {
             if (blacklisted((char*)options->compare[i].name)) continue;
             if (options->compare[i].type == GRIB_NAMESPACE) {
-                iter=grib_keys_iterator_new(h1,0,(char*)options->compare[i].name);
+                iter=grib_keys_iterator_new(h1,0,options->compare[i].name);
                 if (!iter) {
                     printf("ERROR: unable to get iterator\n");
                     exit(1);
@@ -1127,7 +1127,7 @@ static int compare_handles(grib_handle* h1,grib_handle* h2,grib_runtime_options*
             for (i=0; i< options->compare_count; i++) {
                 if (blacklisted(name)) continue;
                 if (options->compare[i].type == GRIB_NAMESPACE) {
-                    iter=grib_keys_iterator_new(h1,0,(char*)options->compare[i].name);
+                    iter=grib_keys_iterator_new(h1,0,options->compare[i].name);
                     if (!iter) {
                         printf("ERROR: unable to get iterator for %s\n",options->compare[i].name );
                         exit(1);