Double-precision floating point numbers

Functions
QDB_API_LINKAGE qdb_error_t	qdb_double_put (qdb_handle_t handle, const char *alias, double value, qdb_time_t expiry_time)
	Creates a new double-precision floating point number. More...
QDB_API_LINKAGE qdb_error_t	qdb_double_update (qdb_handle_t handle, const char *alias, double value, qdb_time_t expiry_time)
	Creates or updates a double-precision floating point number. More...
QDB_API_LINKAGE qdb_error_t	qdb_double_get (qdb_handle_t handle, const char *alias, double *value)
	Retrieves the value of a double-precision floating point number. More...
QDB_API_LINKAGE qdb_error_t	qdb_double_add (qdb_handle_t handle, const char *alias, double addend, double *result)
	Atomically increases or decreases a double-precision floating point number. More...

Detailed Description

Function Documentation

QDB_API_LINKAGE qdb_error_t qdb_double_add	(	qdb_handle_t	handle,
		const char *	alias,
		double	addend,
		double *	result
	)

Atomically increases or decreases a double-precision floating point number.

The specified entry will be atomically increased (or decreased) according to the given addend value:

• To increase the value, specify a positive addend
• To decrease the value, specify a negative addend

The function return the result of the operation.

The entry must already exist. If the entry is not a double, the function will return qdb_e_incompatible_type.

Parameters

handle	A valid handle previously initialized by qdb_open or qdb_open_tcp.
alias	A pointer to a null-terminated UTF-8 string representing the alias of the entry.
addend	The value to add to the existing value.
result	A pointer to a double that will receive the current value of the entry, if successful.

Returns

A qdb_error_t code indicating success or failure.

See Also

qdb_double_put, qdb_double_update, qdb_double_get

QDB_API_LINKAGE qdb_error_t qdb_double_get	(	qdb_handle_t	handle,
		const char *	alias,
		double *	value
	)

Retrieves the value of a double-precision floating point number.

Atomically retrieves the value of an existing double-precision floating point number.

If the entry is not a double, the function will return qdb_e_incompatible_type.

Parameters

handle	A valid handle previously initialized by qdb_open or qdb_open_tcp.
alias	A pointer to a null-terminated UTF-8 string representing the alias of the entry.
value	A pointer to a number that will receive the current value of the entry, if successful.

Returns

A qdb_error_t code indicating success or failure.

See Also

qdb_double_put, qdb_double_update, qdb_double_add

QDB_API_LINKAGE qdb_error_t qdb_double_put	(	qdb_handle_t	handle,
		const char *	alias,
		double	value,
		qdb_time_t	expiry_time
	)

Creates a new double-precision floating point number.

Atomically creates an entry of the given alias and sets it to a cross-platform double-precision floating point number. If the entry already exists, the function returns an error.

You can specify an expiry or use qdb_never_expires if you don't want the entry to expire.

If you want to create or update an entry use qdb_double_update.

The value will be correctly translated independently of the endianness of the client's platform.

Parameters

handle	A valid handle previously initialized by qdb_open or qdb_open_tcp.
alias	A pointer to a null-terminated UTF-8 string representing the alias of the entry.
value	The value to which the number must be set.
expiry_time	An optional absolute expiry time expressed in UTC UNIX epoch.

Returns

A qdb_error_t code indicating success or failure.

See Also

qdb_double_update, qdb_double_get, qdb_double_add

QDB_API_LINKAGE qdb_error_t qdb_double_update	(	qdb_handle_t	handle,
		const char *	alias,
		double	value,
		qdb_time_t	expiry_time
	)

Creates or updates a double-precision floating point number.

Atomically updates an entry of the given alias to the provided value. If the entry doesn't exist, it will be created. If the entry is not a double, the function will return qdb_e_incompatible_type.

You can specify an expiry time or use qdb_never_expires if you don't want the entry to expire.

Parameters

handle	A valid handle previously initialized by qdb_open or qdb_open_tcp.
alias	A pointer to a null-terminated UTF-8 string representing the alias of the entry.
value	The value to which the number must be set.
expiry_time	An optional absolute expiry time expressed in UTC UNIX epoch.

Returns

A qdb_error_t code indicating success or failure.

See Also

qdb_double_put, qdb_double_get, qdb_double_add