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c-treeDB API for C# - Developers Guide

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CTBase.GetSystemConfig

Declaration

LONG GetSystemConfig( NINT index );

Description

GetSystemConfig() retrieves c-tree Plus system configuration values, as well as some of the important dynamic aspects of the system, such as the memory usage and the number of files in use. To determine if a particular system configuration option is active, call GetSystemConfig(), passing the corresponding pre-define constant for that option, and check if the value returned is non-zero.

The following pre-defined constant should be passed to GetSystemConfig():

Constant

Description

cfgMEMORY_USAGE

Current system memory usage.

cfgMEMORY_HIGH

Highest system memory use.

cfgNET_ALLOCS

Current system net allocations. (Number of memory allocations minus the number of free calls.)

cfgOPEN_FILES

FairCom DB files opened by system.

cfgPHYSICAL_FILES

Physical FairCom DB files open. Includes c-tree Superfile members omitted from cfgOPEN_FILES count.

cfgOPEN_FCBS

FairCom DB file control blocks in use by system.

cfgLOGIDX

Is file mode ctLOGIDX supported?

The following constants only apply to client-server implementations:

Constant

Description

cfgDNODE_QLENGTH

Messages in delete node queue.

cfgCHKPNT_QLENGTH

Messages in checkpoint queue.

cfgSYSMON_QLENGTH

Messages in system monitor queue.

cfgLOGONS

Current number of logons.

cfgNET_LOCKS

Current number of pending locks (system wide).

cfgUSERS

Maximum number of logons.

cfgMAX_CONNECT

The limit for the maximum number of logons.

cfgUSER_FILES

Number of FairCom DB files opened by calling user.

cfgUSER_MEMORY

Current user memory usage.

cfgPATH_SEPARATOR

ASCII value for the file name path separator.

The following constants are static compile time values:

Constant

Description

cfgFILES

Maximum number of c-tree Plus file control blocks available system wide.

cfgMAX_DAT_KEY

Maximum number of indices per data file.

cfgMAX_KEY_SEG

Maximum number of key segments per index.

The constants above and the pre-initialization resources section below have client and c-tree Server versions, except for the following three subscripts:

Constant

Description

cfgINIT_CTREEapp

Determine whether FairCom DB has been initialized.

cfgSERIALNBR

The c-tree Server serial number.

cfgTHREADapp

Indicates if threading has been enabled.

Constants ending with ‘app’ are specific to the client side of a client/server application. To check the same system setting for the c-tree Server, use the same subscript without the app extension. For example, to determine if Conditional Index support is active on the c-tree Server, use cfgCONDIDX as the subscript and cfgCONDIDXapp for the client side.

Constant

Description

cfgBOUNDapp

Indicates if the application is bound to a database library. See the discussion on the different FairCom I/O models in these notes.

cfgDISKIO_MODELapp

A non-zero value indicates a stand-alone multi-user I/O model i.e. FPUTFGET.

cfgLOCLIBapp

A non-zero value indicates Local Library support.

cfgNOGLOBALSapp

A non-zero value indicates no globals are supported, that is, indicating all globals are stored in an allocated structure. This is the default setting.

cfgUNIFRMATapp

A non-zero value indicates FairCom's automatic byte flipping (UNIFRMAT) is active.

The pre-initialization resource constants below may be specified prior to a c-treeDB initialization call, i.e ctdbLogon(), CTSession::Logon(), or CTSession.Logon(), in addition to having both a client and c-tree Server version, as discussed above.

Constant

Description

cfgANSIapp

Specifies whether to use ANSI. A non-zero value indicates ANSI.

cfgCONDIDXapp

A non-zero value indicates the application supports. FairCom's Conditional Index Logic.

cfgCTBATCHapp

A non-zero value indicates the application supports. Batch Operations.

cfgCTSUPERapp

A non-zero value indicates the application supports c-tree Superfiles.

cfgCTS_ISAMapp

A non-zero value indicates the application supports FairCom's ISAM API.

cfgHISTORYapp

A non-zero value indicates the application supports FairCom's History Logic.

cfgINIT_CTREEapp

A non-zero value indicates FairCom DB has been initialized.

cfgLOGIDXapp

A non-zero value indicates the application supports the ctLOGIDX Logic.

cfgPARMFILEapp

A non-zero value indicates parameter files are supported.

cfgPASCAL24app1

A non-zero value indicates 2-byte/4-byte length delimited strings are using the traditional pascal length convention.

cfgPASCALstapp1

A non-zero value indicates byte length delimited strings are using the traditional pascal length convention.

cfgPATH_SEPARATORapp

Return the ASCII value for the file name path separator.

cfgPROTOTYPEapp

A non-zero value indicates the application supports Prototypes.

cfgRESOURCEapp

A non-zero value indicates the application supports Resource Records.

cfgRTREEapp

A non-zero value indicates the application supports the r-tree report engine.

cfgSERIALNBR

Return c-tree Server serial number.

cfgTHREADapp

A non-zero value indicates the application supports FairCom's threading API.

cfgTRANPROCapp

A non-zero value indicates the application supports Transaction Processing.

cfgVARLDATAapp

A non-zero value indicates the application supports Variable Length Records.

cfgVARLKEYSapp

A non-zero value indicates the application supports Variable Length Keys i.e. Key compression.

cfgWORD_ORDERapp

Indicates the client data order: Low_High or High_Low. A non-zero value indicates Low_High.

1Pascal length byte

FairCom DB supports two different methods for specifying the length byte in a pascal data type. The original and non-traditional approach does not include the length byte in the byte count. For example, with a 1-byte data type, CT_FPSTRING, the smallest valid length byte would be 0. The new method follows the more traditional pascal convention of including the length byte in the byte count. For example, with the traditional approach, the smallest valid length for a 1-byte data type would be 1. Therefore, if cfgPASCALstapp or cfgPASCAL24app return a non-zero value, the new traditional approach is active.

To receive a valid return value from cfgPATH_SEPARATOR, ctPATH_SEP must be defined. The default definition found in ctopt2.h is:

#define ctPATH_SEP '?'

This definition specifies that the system default path separator will be used. To use the same separator for all platforms, you might want to choose one of the following:

#define ctPATH_SEP '\\'

/* define for Windows */

#define ctPATH_SEP '/'

/* define for most Unix systems */

#define ctPATH_SEP ':'

/* define for Mac OSX */

/* where the Uninitialized value is NINT_ERR for a client or FINT_ERR for a bound application */

The following constants can be used to capture system-wide cache and buffer statistics, (cache pages hold data record images and buffers hold index nodes), allowing an application to track the use of these resources.

Constant

Description

cfgCACHE_PAGES

Available cache pages

cfgCACHE_PAGES_INUSE

Cache pages in use

cfgCACHE_PAGES_MXUSE

Maximum cache pages used

cfgCACHE_PAGES_DED

Available dedicated cache pages

cfgCACHE_PAGES_DEDINUSE

Dedicated cache pages in use

cfgCACHE_PAGES_DEDMXUSE

Maximum dedicated cache pages used

cfgBUFFER_PAGES

Available index buffers

cfgBUFFER_PAGES_INUSE

Index buffers in use

cfgBUFFER_PAGES_MXUSE

Maximum index buffers used

Return Values

Returns a value that depends on the configuration constant passed to GetSystemConfig().

Example

The following example checks if TRANPROC was turned on during system compilation.
// check if TRANPROC was turned on

if (hSession.GetSystemConfig( ctTRANPROC ))

printf("TRANPROC was turned on during compilation\n");

else

printf("TRANPROC was turned off during compilation\n");

See Also

TOCIndex