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is a pointer to a variable that contains an error code returned by this function. Possible values are:
OS_ERR_NONE
if If the call was successful and the caller was returned the value.
OS_ERR_OS_NOT_RUNNING
if If you called OS_TLS_GetValue() and the kernel has not started yet. However, it’s acceptable to call this function prior to starting multitasking but in this case, you must specify a non-NULL pointer for p_tcb.
OS_ERR_TLS_ID_INVALID
if If you called OS_TLS_GetValue() and specified a TLS ID that has not been assigned. See OS_TLS_GetID() about assigning TLS IDs.
OS_ERR_TLS_NOT_EN
if If you called OS_TLS_GetValue() but the task was created with the option OS_OPT_TASK_NO_TLS indicating that the task does not need TLS support.
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