nvs_get_i8() function

get int8_t value for given key These functions retrieve value for the key, given its name. If \c key does not exist, or the requested variable type doesn't match the type which was used when setting a value, an error is returned. In case of any error, out_value is not modified. \c out_value has to be a pointer to an already allocated variable of the given type.

{c}
 // Example of using nvs_get_i32:
 int32_t max_buffer_size = 4096; // default value
 esp_err_t err = nvs_get_i32(my_handle, "max_buffer_size", &max_buffer_size);
 assert(err == ESP_OK || err == ESP_ERR_NVS_NOT_FOUND);
 // if ESP_ERR_NVS_NOT_FOUND was returned, max_buffer_size will still
 // have its default value.
 

Syntax

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Summary

Declaration

Definition

from nvs.h:385

esp_err_t nvs_get_i8 (nvs_handle_t handle, const char* key, int8_t* out_value);

Implemented in nvs_api.cpp:459

Arguments

Argument

Description

handle

Handle obtained from nvs_open function.

key

Key name. Maximum length is (NVS_KEY_NAME_MAX_SIZE-1) characters. Shouldn't be empty.

out_value

Pointer to the output value. May be NULL for nvs_get_str and nvs_get_blob, in this case required length will be returned in length argument.

Return value

- ESP_OK if the value was retrieved successfully - ESP_FAIL if there is an internal error; most likely due to corrupted NVS partition (only if NVS assertion checks are disabled) - ESP_ERR_NVS_NOT_FOUND if the requested key doesn't exist - ESP_ERR_NVS_INVALID_HANDLE if handle has been closed or is NULL - ESP_ERR_NVS_INVALID_NAME if key name doesn't satisfy constraints - ESP_ERR_NVS_INVALID_LENGTH if length is not sufficient to store data

Examples

nvs_get_i8() is referenced by 3 libraries and example projects:

References

from examples

nvs_get_i8() function

Syntax

Arguments

Return value

Examples

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