gln_retrieve_balances

Declared in <galanthus/c_api/gln_capi.h>.

GLN_API gln_status_t GLN_CALL gln_retrieve_balances(
    gln_backend_t*                     in_backend,
    const gln_list_balances_request_t* in_request,
    gln_backend_result_t**             out_result);

Family: Backend operations
Return type: gln_status_t

Purpose

gln_retrieve_balances asks a backend for balances for one account IBAN and returns a gln_backend_result_t envelope.

Success rows expose the account IBAN, amount, currency, status, and optional as-of date/time, product, pending amount, credit-line, availability, overdraft, and due-date fields when the provider supplies them.

Backend support is operation-specific. Use gln_check_backend_operation_support to check whether a backend supports this operation before calling it. Unsupported operations return an envelope whose status is GLN_ERR_NOT_SUPPORTED.

When To Use

Use this operation after choosing an account row from gln_retrieve_accounts or an embedded account from gln_retrieve_bank_info.

Pass the account IBAN from gln_get_account_iban; do not pass display-only account labels such as product name or owner.

Call Contract

GLN_OK from the function means an envelope was produced in *out_result; it does not mean the backend operation succeeded. Inspect the envelope with gln_get_backend_result_outcome, gln_get_backend_result_status, and gln_get_backend_result_kind.

out_result == NULL is the no-envelope invalid-argument case. In that case the function returns GLN_ERR_INVALID_ARG directly.

For gln_list_balances_request_t, iban is required and must be non-empty.

The parameter table is binding for required handles and output slots.

Return

Returns GLN_OK when the call produced a gln_backend_result_t envelope in out_result. Operation success, caller action, provider rejection, and operation errors are reported inside that envelope.

Type	Nullability	Ownership
`gln_status_t`	value	value

Parameters

Name	Direction	Type	Nullability	Ownership
`in_backend`	input	`gln_backend_t*`	nonnull	borrowed
`in_request`	input	`const gln_list_balances_request_t*`	nonnull	borrowed
`out_result`	output	`gln_backend_result_t**`	nonnull	transferred_out

Success Result

Successful operation envelopes have outcome GLN_BACKEND_OUTCOME_SUCCESS, status GLN_OK, and kind GLN_BACKEND_RESULT_KIND_BALANCES.

Borrow the typed success view with gln_get_backend_result_balances.

Use gln_get_backend_result_balances only when the envelope outcome is GLN_BACKEND_OUTCOME_SUCCESS and the kind is GLN_BACKEND_RESULT_KIND_BALANCES.

Action-required envelopes carry interrupt details and a continuation instead of this typed success view. Resume the operation and read the accessor only after a success envelope is produced.

gln_get_balance_amount, gln_get_balance_currency, and gln_get_balance_status return the booked balance fields. Optional balance fields return NULL when the provider did not supply that value for the row.

Outcomes

GLN_BACKEND_OUTCOME_SUCCESS: read the GLN_BACKEND_RESULT_KIND_BALANCES typed view.
GLN_BACKEND_OUTCOME_ACTION_REQUIRED: FinTS read flows can require caller action, usually a TAN or decoupled step. Inspect gln_get_backend_result_interrupt_info, take the continuation with gln_take_backend_result_continuation, and resume with gln_resume_continuation.
GLN_BACKEND_OUTCOME_REJECTED: inspect gln_get_backend_result_status and gln_get_backend_result_error for provider rejection details.
GLN_BACKEND_OUTCOME_ERROR: inspect gln_get_backend_result_status and gln_get_backend_result_error. Other backends use this outcome with status GLN_ERR_NOT_SUPPORTED.

Ownership And Lifetime

The envelope returned through out_result is caller-owned and must be released with gln_destroy_backend_result.

Typed views, result rows or fields, borrowed strings, and the JSON string are borrowed from the envelope. They become invalid when the envelope is destroyed. Copy strings or row data before destroying the envelope when the caller needs to keep them.

For action-required envelopes, gln_get_backend_result_interrupt_info returns borrowed interrupt details. gln_take_backend_result_continuation transfers continuation ownership to the caller; destroy that continuation with gln_destroy_continuation after it has been saved or resumed.