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Fix: nvs docs Programmers guide #1803

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Fix: nvs docs Programmers guide #1803

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16 changes: 8 additions & 8 deletions doc/src/programmers-guide.md
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Expand Up @@ -1085,36 +1085,36 @@ storage, as the flash storage may degrade more rapidly with repeated writes to t

NVS entries are stored under a namespace and key, both of which are expressed as atoms. AtomVM uses the namespace `atomvm` for entries under its control. Applications may read from and write to the `atomvm` namespace, but they are strongly discouraged from doing so, except when explicitly stated otherwise.

To set a value in non-volatile storage, use the [`esp:nvs_set_binary/3`](./apidocs/erlang/eavmlib/esp.md#nvs_set_binary3) function, and specify a namespace, key, and value:
To set a value in non-volatile storage, use the [`esp:nvs_put_binary/3`](./apidocs/erlang/eavmlib/esp.md#nvs_put_binary3) function, and specify a namespace, key, and value:

```erlang
Namespace = <<"my-namespace">>,
Key = <<"my-key">>,
esp:set_binary(Namespace, Key, <<"some-value">>).
Namespace = my_namespace_atom,
Key = my_key_atom,
esp:nvs_put_binary(Namespace, Key, <<"some-value">>).
```

To retrieve a value in non-volatile storage, use the [`esp:nvs_get_binary/2`](./apidocs/erlang/eavmlib/esp.md#nvs_get_binary2) function, and specify a namespace and key. You can optionally specify a default value (of any desired type), if an entry does not exist in non-volatile storage:

```erlang
Value = esp:get_binary(Namespace, Key, <<"default-value">>).
Value = esp:nvs_get_binary(Namespace, Key, <<"default-value">>).
```

To delete an entry, use the [`esp:nvs_erase_key/2`](./apidocs/erlang/eavmlib/esp.md#nvs_erase_key2) function, and specify a namespace and key:

```erlang
ok = esp:erase_key(Namespace, Key).
ok = esp:nvs_erase_key(Namespace, Key).
```

You can delete all entries in a namespace via the [`esp:nvs_erase_all/1`](./apidocs/erlang/eavmlib/esp.md#nvs_erase_all1) function:

```erlang
ok = esp:erase_all(Namespace).
ok = esp:nvs_erase_all(Namespace).
```

Finally, you can delete all entries in all namespaces on the NVS partition via the [`esp:nvs_reformat/0`](./apidocs/erlang/eavmlib/esp.md#nvs_reformat0) function:

```erlang
ok = esp:reformat().
ok = esp:nvs_reformat().
```

Applications should use the `esp:nvs_reformat/0` function with caution, in case other applications are making using the non-volatile storage.
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