NDS2 access functions.

enum	chantype {   cUnknown, cOnline, cRaw, cRDS,   cSTrend, cMTrend, cTestPoint, cStatic,   cSimData }
	Channel type code enumerator. More...
typedef enum chantype	chantype_t
	Channel type code enumerator. More...
enum	nds_version { nds_try = 0, nds_v1 = 1, nds_v2 = 2 }
typedef struct daq_block_header	daq_block_t
DLL_EXPORT int	daq_clear_channel_list (daq_t *daq)
	Clear the channel list. More...
DLL_EXPORT int	daq_connect (daq_t *daq, const char *host, int port, enum nds_version version)
	Make a connection to an NDS server. More...
DLL_EXPORT void	daq_destroy (daq_t *daq)
	Close and delete all client status structure elements. More...
DLL_EXPORT int	daq_disconnect (daq_t *daq)
	Disconnect from the server. More...
DLL_EXPORT const char *	daq_get_channel_addr (daq_t *daq, const char *channel)
	Get a pointer to the data for the specified channel. More...
DLL_EXPORT char *	daq_get_channel_data (daq_t *daq, const char *channel, char *data)
	Copy channel data. More...
DLL_EXPORT int	daq_get_data_length (daq_t *daq, const char *channel)
	Get the channel data length. More...
DLL_EXPORT chan_req_t *	daq_get_channel_status (daq_t *daq, const char *channel)
	Get a pointer to channel data. More...
DLL_EXPORT int	daq_get_last_message (daq_t *daq, char *buf, size_t max_len, int *len)
	Get the last message. More...
DLL_EXPORT int	daq_get_scaled_data (daq_t *daq, const char *channel, float *data)
	Calibrate and copy channel data. More...
DLL_EXPORT void	daq_init (daq_t *daq)
	Initialize a daq_t structure. More...
DLL_EXPORT void	daq_init_channel (daq_channel_t *chan, const char *name, enum chantype ctype, double rate, daq_data_t dtype)
	Initialize a daq_channel_t structure. More...
DLL_EXPORT int	daq_is_connected (daq_t *daq)
	Test for connected server. More...
DLL_EXPORT int	daq_recv_block_num (daq_t *daq)
	Receive block number. More...
DLL_EXPORT int	daq_recv_block (daq_t *daq)
	Receive a data block. More...
DLL_EXPORT int	daq_recv_next (daq_t *daq)
	Receive a data block. More...
DLL_EXPORT int	daq_recv_shutdown (daq_t *daq)
	Close the client connection. More...
DLL_EXPORT int	daq_recv_channels (daq_t *daq, daq_channel_t *channel, int num_channels, int *num_channels_received)
	Get a list of online channels. More...
DLL_EXPORT int	daq_recv_channel_hash (daq_t *daq, void *hash, int *length, time_t gps, enum chantype type)
	Get a channel list hash. More...
DLL_EXPORT int	daq_recv_hash_by_pattern (daq_t *daq, void *hash, int *length, time_t gps, enum chantype type, const char *pat)
	Get a channel list hash. More...
DLL_EXPORT int	daq_recv_channel_list (daq_t *daq, daq_channel_t *channel, int num_channels, int *num_channels_received, time_t gps, enum chantype type)
	Get a list of channels. More...
DLL_EXPORT int	daq_recv_channels_by_pattern (daq_t *daq, daq_channel_t *channel, int num_channels, int *num_channels_received, time_t gps, enum chantype type, const char *pat)
	Get a list of channels. More...
DLL_EXPORT int	daq_recv_epoch_list (daq_t *daq, char *epochs, size_t max_len, int *str_len)
	Get a list of epochs. More...
DLL_EXPORT long	daq_recv_id (daq_t *daq)
	Receive an ID. More...
DLL_EXPORT int	daq_recv_source_data (daq_t *daq, char *sources, size_t max_len, time_t gps, long *str_len)
	Get a list of source frames. More...
DLL_EXPORT int	daq_recv_source_list (daq_t *daq, char *sources, size_t max_len, time_t gps, long *str_len)
	Get a list of source frames. More...
DLL_EXPORT int	daq_request_channel (daq_t *daq, const char *name, enum chantype type, double rate)
	Add a channel to the request list. More...
DLL_EXPORT int	daq_request_channel_from_chanlist (daq_t *daq, daq_channel_t *channel)
	Add a channel to the request list. More...
DLL_EXPORT int	daq_request_check (daq_t *daq, time_t start, time_t end)
	Check requested data. More...
DLL_EXPORT int	daq_request_data (daq_t *daq, time_t start, time_t end, time_t dt)
	Get requested data. More...
DLL_EXPORT int	daq_send (daq_t *daq, const char *command)
	send a command string. More...
DLL_EXPORT int	daq_set_epoch (daq_t *daq, const char *epoch)
	Set the default epoch. More...
DLL_EXPORT int	daq_startup (void)
	Initialize nds1/nds2 client subsystems. More...
DLL_EXPORT const char *	daq_strerror (int errornum)
	determine English equivalent of return code. More...
DLL_EXPORT uint4_type	daq_get_block_secs (daq_t *daq)
DLL_EXPORT uint4_type	daq_get_block_gps (daq_t *daq)
DLL_EXPORT uint4_type	daq_get_block_gpsn (daq_t *daq)
DLL_EXPORT uint4_type	daq_get_block_seq_num (daq_t *daq)
DLL_EXPORT char *	daq_get_block_data (daq_t *daq)
#define	HEADER_LEN   16

Detailed Description

This module defines the NDS2 API. The C-functions provide a backward- compatible low level interface that may be used with either version of the NDS. These may used to implement the client server protocol defined elsewhere, e.g. classic NDS protocol or NDS protocol. A second high level interface is new to the API. This allows the user to make the server requests to either version of the NDS and without knowledge of the server protocol.

Macro Definition Documentation

#define HEADER_LEN   16

Block header structure length.

Typedef Documentation

typedef enum chantype chantype_t

Channel type code enumerator.

Define channel types. The channel types are used to distinguish the requested source of the data.

Remarks

This expands on and replaces the channel group code in the NDS1 API which seems to have a very few values (0=normal fast channel, 1000=dmt trend channel, 1001=obsolete dmt channel).

typedef struct daq_block_header daq_block_t

Block header data type

Enumeration Type Documentation

enum chantype

Channel type code enumerator.

Define channel types. The channel types are used to distinguish the requested source of the data.

Remarks

This expands on and replaces the channel group code in the NDS1 API which seems to have a very few values (0=normal fast channel, 1000=dmt trend channel, 1001=obsolete dmt channel).

Enumerator
cUnknown	Unknown or unspecified default type.
cOnline	Online channel
cRaw	Archived raw data channel
cRDS	Processed/RDS data channel
cSTrend	Second trend data
cMTrend	Minute trend data
cTestPoint	test point data
cStatic	FrStat calibration data
cSimData	FrSimData simulated data

enum nds_version

NDS version enumerator

Enumerator
nds_try	Try nds2 first, revert to nds1 on failure
nds_v1	nds1 server protocol
nds_v2	nds2 server protocol

Function Documentation

DLL_EXPORT int daq_clear_channel_list

(

daq_t *

daq

)

Clear the channel list.

Zero the number of requested channels. The number of allocated channel requests is not affected.

Parameters

daq	Pointer to client status structure.

Returns

DAQD status code (always DAQD_OK).

DLL_EXPORT int daq_connect	(	daq_t *	daq,
		const char *	host,
		int	port,
		enum nds_version	version
	)

Make a connection to an NDS server.

Connect to the DAQD server on the host identified by `ip' address. A socket is created using a socket() function call. The host address is found using the gethostbyname() function and a connection is established. The server is then asked for the protocol version and revision with "version;" and "revision;" commands. The version/revision are saved in the client structure.

Parameters

daq	Client status structure/
host	Server host name string.
port	Server port number.
version	NDS version (nds_v1 or nds_v2).

Returns

zero if successful or DAQD status code.

DLL_EXPORT void daq_destroy

(

daq_t *

daq

)

Close and delete all client status structure elements.

daq_destroy closes all open sockets and deletes all member elements of the specified daq_t structure. This function is safe for cleaning up a connection after a fatal error.

Parameters

daq	Pointer to client status structure.

DLL_EXPORT int daq_disconnect

(

daq_t *

daq

)

Disconnect from the server.

Disconnect from the server by sending a "quit;" command and close the socket file descriptor.

Parameters

daq	Pointer to client status structure.

Returns

DAQD status code.

DLL_EXPORT char* daq_get_block_data

(

daq_t *

daq

)

Return starting address of the data in the block.

Parameters

daq	Pointer to client status structure.

Returns

Pointer to data portion of block.

DLL_EXPORT uint4_type daq_get_block_gps

(

daq_t *

daq

)

Return time stamp second field of the first sample in the block

Parameters

daq	Pointer to client status structure.

Returns

Block start gps.

DLL_EXPORT uint4_type daq_get_block_gpsn

(

daq_t *

daq

)

Return time stamp nano-second field of the first sample in the block

Parameters

daq	Pointer to client status structure.

Returns

Block start time offset in nano-seconds.

DLL_EXPORT uint4_type daq_get_block_secs

(

daq_t *

daq

)

Return the number of seconds spanned by the data in the block.

Parameters

daq	Pointer to client status structure.

Returns

Block length in seconds.

DLL_EXPORT uint4_type daq_get_block_seq_num

(

daq_t *

daq

)

Return the block sequence number; shows if any blocks were dropped.

Parameters

daq	Pointer to client status structure.

Returns

Block Sequence number.

DLL_EXPORT const char* daq_get_channel_addr	(	daq_t *	daq,
		const char *	channel
	)

Get a pointer to the data for the specified channel.

Get a pointer to the data block from a specified channel name. Note that the returned address is in the daqd temporary buffer. It is likely that the data will be replaced during the next call to the daq_recv_next and possible that the data for the requested channel will be in a different location after the next request. If an error occurred in fetching the data, the returned pointer is NULL and the error code is stored in the daq->err_num.

Parameters

daq	Pointer to client status structure.
channel	Pointer to null terminated channel name string.

Returns

Pointer to channel data or NULL.

DLL_EXPORT char* daq_get_channel_data	(	daq_t *	daq,
		const char *	channel,
		char *	data
	)

Copy channel data.

Copy the data from a specified channel name to the target address. The target buffer must be large enough for the full data record. If the requested data are not available a NULL pointer is returned and the error code is stored in daq->err_num.

Parameters

daq	Pointer to client status structure.
channel	Pointer to null terminated channel name string.
data	pointer to a buffer to receive channel data.

Returns

Pointer to channel data buffer or NULL.

DLL_EXPORT chan_req_t* daq_get_channel_status	(	daq_t *	daq,
		const char *	channel
	)

Get a pointer to channel data.

Get a pointer specified channel request/status block.

Parameters

daq	Pointer to client status structure.
channel	Pointer to null terminated channel name string.

Returns

Pointer to channel request/status structure.

DLL_EXPORT int daq_get_data_length	(	daq_t *	daq,
		const char *	channel
	)

Get the channel data length.

Get the number of bytes of data retrieved for the specified channel.

Parameters

daq	Pointer to client status structure.
channel	Pointer to null terminated channel name string.

Returns

Number of data bytes or 0 if channel not found.

DLL_EXPORT int daq_get_last_message	(	daq_t *	daq,
		char *	buf,
		size_t	max_len,
		int *	len
	)

Get the last message.

Last error message from the server.

Parameters

daq	Pointer to client status structure.
buf	Buffer to receive null terminated message string.
max_len	length of buf.
len	pointer to int to receive length of message.

Returns

Number of message bytes or -1.

DLL_EXPORT int daq_get_scaled_data	(	daq_t *	daq,
		const char *	channel,
		float *	data
	)

Calibrate and copy channel data.

Copy the data from a specified channel name to the target address. The data are converted to floats and scaled according to the linear transform specified by the NDS server. Complex data are not copied converted or scaled. The number of output data words is returned. It is up to the user to insure that the output array is large enough to accommodate the data.

Parameters

daq	Pointer to client status structure.
channel	Pointer to null terminated channel name string.
data	pointer to a buffer to receive calibrated channel data.

Returns

Number of data words copied.

DLL_EXPORT void daq_init

(

daq_t *

daq

)

Initialize a daq_t structure.

All elements of a specified daq_t structure are set to their NULL values.

Parameters

daq	Pointer to client status structure.

DLL_EXPORT void daq_init_channel	(	daq_channel_t *	chan,
		const char *	name,
		enum chantype	ctype,
		double	rate,
		daq_data_t	dtype
	)

Initialize a daq_channel_t structure.

Initialize a daq_channel_t structure with the specified data. If the channel type is _unknown and the name contains a trend channel suffix (e.g. .mean ) the type will be reset to a trend type in accordance with the specified rate. Trend channels are assigned a rate and data_type appropriate to the trend type. If a trend-type channel does not have an appropriate suffix, ".mean" is appended to the channel name.

Parameters

chan	Pointer to structure to be initialized
name	Channel name
ctype	Channel type code
rate	Sample rate
dtype	Data type.

DLL_EXPORT int daq_is_connected

(

daq_t *

daq

)

Test for connected server.

Test whether the socket is connected.

Parameters

daq	Pointer to client status structure.

Returns

Client is connected if non-zero.

DLL_EXPORT int daq_recv_block

(

daq_t *

daq

)

Receive a data block.

Receive one data block (data channel samples). A transmission buffer is allocated as needed and its pointer is assigned to `daq->tb'. The block size is assigned to `daq->tb_size'. A zero length block consists of the block header and no data. It is sent by the server when it fails to find the data for the GPS second, specified in the block header (Note: this can only happen for the off-line data request). If channel reconfiguration has occurred, the server sends a special reconfiguration data block. For the client it means he needs to reread channel data conversion variables and status from the *daq structure.

Parameters

daq	Pointer to client status structure.

Returns

• >0: Number bytes of sample data read
• 0: Zero length data block is received
• -1: Error
• -2: Channel reconfiguration

DLL_EXPORT int daq_recv_block_num

(

daq_t *

daq

)

Receive block number.

Receive a data block number or zero for online data.

Parameters

daq	Pointer to client status structure.

Returns

Block number or -1 on error.

DLL_EXPORT int daq_recv_channel_hash	(	daq_t *	daq,
		void *	hash,
		int *	length,
		time_t	gps,
		enum chantype	type
	)

Get a channel list hash.

Get a channel list hash for the specified channel type and gps time. The gps and type parameters are interpreted exactly as for the daq_recv_channel_list() function. The preliminary hash code implementation is a crc-32 so the length of the hash buffer must be at least 4 bytes. If the hashing scheme changes a longer buffer may be required.

Parameters

daq	Pointer to client status structure.
hash	Pointer to a buffer to receive the hash code.
length	Pointer to integer that on entry contains the length of the hash buffer and on return contains the length of the receved hash code.
gps	validity time (or zero for current channels)
type	Limit hash to include only channels of the specified type.

Returns

DAQD status code.

DLL_EXPORT int daq_recv_channel_list	(	daq_t *	daq,
		daq_channel_t *	channel,
		int	num_channels,
		int *	num_channels_received,
		time_t	gps,
		enum chantype	type
	)

Get a list of channels.

Get a list of channel names and information. A list of all channels available at the specified time and of the specified type is returned. A GPS time of zero indicates currently available channels. A type code of cUnknown (0) gives all channel types available at the specified gps time. Note that this will produce a list with multiple channel entries with identical names. The number of channels returned in *num_channels_received is the total number of channels available from the server and may exceed the number of channels for which space has been allocated. In fact, an efficient way to find out how much space is needed for the channel list is to call daq_recv_channel_list with num_channels set to zero and the channel list pointer set to NULL.

Remarks

This function only works correctly with the NDS2 server. If a non-zero GPS or a data type other than cOnline is requested, the function returns DAQD_VERSION_MISMATCH and *num_channels_received is set to zero.

Parameters

daq	Pointer to client status structure.
channel	List of daq_channel structures to receive information.
num_channels	Number of channel structures allocated.
num_channels_received	Pointer to integer to receive number of channels defined on server (may exceed num_channels ).
gps	validity time (or zero for current channels)
type	List only channels of the specified type.

Returns

DAQD status code.

DLL_EXPORT int daq_recv_channels	(	daq_t *	daq,
		daq_channel_t *	channel,
		int	num_channels,
		int *	num_channels_received
	)

Get a list of online channels.

Get a list of online channel names and information. daq_recv_channels requests the channel information as appropriate for the server version. All channel data are then copied into the list. This function is included to allow backward compatibility with the classic nds interface and is implemented with a call to daq_recv_channel_list. See the documentation for daq_recv_channel_list for further details.

Parameters

daq	Pointer to client status structure.
channel	List of daq_channel structures to receive information.
num_channels	Number of channel structures allocated.
num_channels_received	Number of channels defined.

Returns

DAQD status code.

DLL_EXPORT int daq_recv_channels_by_pattern	(	daq_t *	daq,
		daq_channel_t *	channel,
		int	num_channels,
		int *	num_channels_received,
		time_t	gps,
		enum chantype	type,
		const char *	pat
	)

Get a list of channels.

Get a list of channel names and information. A list of all channels matching the specified pattern available at the specified time and of the specified type is returned. A GPS time of zero indicates currently available channels. A type code of cUnknown (0) gives all channel types available at the specified gps time. The pattern bash-like channel name template used to select the channels to be matched. A null string will match all channel names.. Note that this function may produce a list with multiple channel entries with identical names. The number of channels returned in *num_channels_received is the total number of channels available from the server and may exceed the number of channels for which space has been allocated. In fact, an efficient way to find out how much space is needed for the channel list is to call daq_recv_channel_list with num_channels set to zero and the channel list pointer set to NULL.

Remarks

This function only works completely with the NDS2 server. If a non-zero GPS or a data type other than cOnline is requested, the function returns DAQD_VERSION_MISMATCH and *num_channels_received is set to zero. Wild-card pattern matching is not currently implemented on the server, althoug an emty string will match all channel names and a non-empty will match achannel with exactly the specified name.

Parameters

daq	Pointer to client status structure.
channel	List of daq_channel structures to receive information.
num_channels	Number of channel structures allocated.
num_channels_received	Pointer to integer to receive number of channels defined on server (may exceed num_channels ).
gps	validity time (or zero for current channels)
type	List only channels of the specified type.
pat	Channel list pattern.

Returns

DAQD status code.

DLL_EXPORT int daq_recv_epoch_list	(	daq_t *	daq,
		char *	epochs,
		size_t	max_len,
		int *	str_len
	)

Get a list of epochs.

Get a list of epoch names and their gps time ranges. The list is returned into a user defined character buffer of spcified length. The number of bytes of data received is returned in a integer length variable specified by the user. The epoch list is a string with blank separated field of the form "\<epoch-name>=\<gps-start>-\<gps-stop>".

Parameters

daq	Pointer to client status structure.
epochs	Character buffer to receive the epoch definition list.
max_len	Length (in bytes) of the allocated buffer.
str_len	Pointer to int to be filled with string length in bytes.

Returns

DAQD status code.

DLL_EXPORT int daq_recv_hash_by_pattern	(	daq_t *	daq,
		void *	hash,
		int *	length,
		time_t	gps,
		enum chantype	type,
		const char *	pat
	)

Get a channel list hash.

Get a channel list hash for the specified channel type and gps time and channel name pattern. The gps, type and pattern parameters are interpreted exactly as for the daq_recv_channels_by_pattern() function. The preliminary hash code implementation is a crc-32 so the length of the hash buffer must be at least 4 bytes. If the hashing scheme changes a longer buffer may be required. This function is implemented only for nds2 clients.

Parameters

daq	Pointer to client status structure.
hash	Pointer to a buffer to receive the hash code.
length	Pointer to integer that on entry contains the length of the hash buffer and on return contains the length of the receved hash code.
gps	validity time (or zero for current channels)
type	Limit hash to include only channels of the specified type.
pat	Channel name pattern.

Returns

DAQD status code.

DLL_EXPORT long daq_recv_id

(

daq_t *

daq

)

Receive an ID.

Receive an eight-digit hex ID.

Parameters

daq	Pointer to client status structure.

Returns

The id or -1

DLL_EXPORT int daq_recv_next

(

daq_t *

daq

)

Receive a data block.

Receive one data block, handle all additional protocol, e.g. channel reconfiguration, and swap bytes according to channel list. Data are stored in the internal buffer. For NDS2 requests, the request list is updated with data length, offset, data type and status of each channel. For NDS1 the request list is updated with the inferred lengths and offsets.

Parameters

daq	Pointer to client status structure.

Returns

DAQD status code.

DLL_EXPORT int daq_recv_shutdown

(

daq_t *

daq

)

Close the client connection.

Close the data connection socket and free the allocated buffers (conversion list and transmission buffer).

Parameters

daq	Pointer to client status structure.

Returns

DAQD status code.

DLL_EXPORT int daq_recv_source_data	(	daq_t *	daq,
		char *	sources,
		size_t	max_len,
		time_t	gps,
		long *	str_len
	)

Get a list of source frames.

Get a list of channel sources for the requested channels at the specified gps time. A GPS time of zero indicates currently available channels.

Remarks

This function only works with the NDS2 server.

Parameters

daq	Pointer to client status structure.
sources	List of daq_channel structures to receive information.
max_len	Pre-allocated string length.
gps	validity time (or zero for current channels)
str_len	Output string length pointer.

Returns

DAQD status code.

DLL_EXPORT int daq_recv_source_list	(	daq_t *	daq,
		char *	sources,
		size_t	max_len,
		time_t	gps,
		long *	str_len
	)

Get a list of source frames.

Get a list of channel sources for the requested channels at the specified gps time. A GPS time of zero indicates currently available channels.

Remarks

This function only works with the NDS2 server.

Parameters

daq	Pointer to client status structure.
sources	List of daq_channel structures to receive information.
max_len	Pre-allocated string length.
gps	validity time (or zero for current channels)
str_len	Output string length pointer.

Returns

DAQD status code.

DLL_EXPORT int daq_request_channel	(	daq_t *	daq,
		const char *	name,
		enum chantype	type,
		double	rate
	)

Add a channel to the request list.

Add the specified channel to the request list. If the type is set to the default value (cUnknown or 0), the channel type will be inferred from the channel name and sample rate as described in the documentation of daq_init_channel. A zero sample rate results in the full-bandwidth data of the specified type.

Parameters

daq	Pointer to client status structure.
name	Pointer to null terminated name string.
type	Channel type.
rate	Requested sampling rate (in Hz).

Returns

DAQD status code.

DLL_EXPORT int daq_request_channel_from_chanlist	(	daq_t *	daq,
		daq_channel_t *	channel
	)

Add a channel to the request list.

Add the specified channel to the request list. The channel name data type, sample rate, etc are copied from the channel list entry.

Parameters

daq	Pointer to client status structure.
channel	Pointer channel list entry.

Returns

DAQD status code.

DLL_EXPORT int daq_request_check	(	daq_t *	daq,
		time_t	start,
		time_t	end
	)

Check requested data.

Request a check on the data status for all channels added to the list for the specified interval.

Parameters

daq	Pointer to client status structure.
start	GPS start time or 0 for online data.
end	GPS end time (see note for NDS1 protocol).

Returns

Server response code.

DLL_EXPORT int daq_request_data	(	daq_t *	daq,
		time_t	start,
		time_t	end,
		time_t	dt
	)

Get requested data.

Request data for all channels added to the list for the specified interval and stride width. Data are received from the start time to the end time in strides of dt seconds. An online data request is made if the start time is zero and only online channels are specified. Online request end times may be specified either as an absolute GPS or as a total data length in seconds (if end is greater than the current time).

Note

The NDS1 protocol ignores the stride length specifier. For online channel requests, the data are sent in 1-second strides starting with the first available time and continuing until the writer is stopped or the connection is broken. For other channel types, the requested stride length is equal to dt=end-start and may be specified either as a non-zero end-time or if end=0, as a dt interval. If the requested data span is longer than an arbitrary maximum (typically 32s) data will be sent in strides of the maximum length.

Parameters

daq	Pointer to client status structure.
start	GPS start time or 0 for online data.
end	GPS end time (see note for NDS1 protocol).
dt	Time stride (see note for NDS1 protocol).

Returns

Server response code.

DLL_EXPORT int daq_send	(	daq_t *	daq,
		const char *	command
	)

send a command string.

Send a null-terminated command string to the server. Then read and return a response code.

Parameters

daq	Pointer to client status structure.
command	Null terminated command text string.

Returns

DAQD status code.

DLL_EXPORT int daq_set_epoch	(	daq_t *	daq,
		const char *	epoch
	)

Set the default epoch.

Set the default epoch for this transaction. The epoch may be defined in any of the following ways.

• An epoch name known to the server, e.g. "S6a".
• A GPS start and end time separated by a hyphen, e.g. "1000000000-1234567890"
• A GPS start time and duration separated by a colon, e.g. "1000000000:234567890"

Parameters

daq	Pointer to client status structure.
epoch	Pointer to epoch string.

Returns

Error code or 0 on success.

Set the default epoch for this session.

DLL_EXPORT int daq_startup

(

void

)

Initialize nds1/nds2 client subsystems.

System initialization.

Returns

Error code or 0 on success.

DLL_EXPORT const char* daq_strerror

(

int

errornum

)

determine English equivalent of return code.

Return string equivalent to a return code.

Parameters

errornum

error return code.

Returns

pointer to static error message string.