MEMVAR UPDATE()
PURPOSE
Update a memory variable
SYNONYM
api_memvar_update()
SYNOPSIS
#include "lianja_api.h" int MEMVAR_UPDATE(name, type, width, decimal, string, number, logical, date) <input parameters> char *name; /* Address of a buffer containing the memory variable name */ char type; /* Memory variable type */ int width; /* Memory variable width */ int decimal; /* Number of decimal places */ char string; /* Address of a buffer containing character string */ double *number; /* Numeric value */ char logical; /* Logical value */ unsigned long date; /* date */ DATETIME datetime; /* datetime */ CURRENCY currency; /* currency */ <output parameters> none
DESCRIPTION
The MEMVAR_UPDATE() function will update a specified memory variable.
Lianja will only recognize the first 32 characters on a memory name as being unique. The memory variable names are not case sensitive and must have been previously defined before updating, or the MEMVAR_UPDATE() function will return a value of -1.
Memory variables can be updated with different data types than they are currently defined. The variable type parameter specifies both the data type and which input parameter value will be used to update the memory variable.
The width parameter is used to specify length of the memory variable. A decimal place can be specified for a number, but should be 0 for other data types.
A memory variable can be defined as any one of the following.
| TYPE | OUTPUT | WIDTH | DESCRIPTION |
|---|---|---|---|
| C | string | 1-8192 | Address of a buffer containing a character string |
| D | date | 8 | Unsigned long representing a Lianja date |
| L | logical | 1 | Character of either 'T' for true or 'F' for false |
| N | number | 1-16 | A value stored in a double |
| T | info_datetime | sizeof(DATETIME) | RCT_DATETIME_DEF structure |
| Y | info_currency | sizeof(CURRENCY) | RCT_CURRENCY_DEF structure |
EXAMPLE
The following example defines six memory variables and then stores the specified values to each variable.
#include "dbapi.h" dbapi_store() { int rc; double numeric; char string[8]; char logical; unsigned long date; DATETIME datetime; CURRENCY currency; strcpy(string, "Tuesday"); date = DATE_CTOD(DATE_DATE()); logical = 'T'; numeric = 23.5; datetime = DATE_STOT(DATE_DATETIME()); currency = CURR_STOY("6474.99"); COMMAND("release all"); MEMVAR_DEFINE( "character", API_PRIVATE ); MEMVAR_DEFINE( "number", API_PRIVATE ); MEMVAR_DEFINE( "logical", API_PRIVATE ); MEMVAR_DEFINE( "date", API_PRIVATE ); MEMVAR_DEFINE( "datetime", API_PRIVATE ); MEMVAR_DEFINE( "currency", API_PRIVATE ); rc = MEMVAR_UPDATE( "character", 'C', 7, 0, string, &numeric, logical, date, datetime, currency); rc = MEMVAR_UPDATE( "number", 'N', 10, 2, string, &numeric, logical, date, datetime, currency); rc = MEMVAR_UPDATE( "logical", 'L', 1, 0, string, &numeric, logical, date, datetime, currency); rc = MEMVAR_UPDATE( "date", 'D', 8, 0, string, &numeric, logical, date, datetime, currency); rc = MEMVAR_UPDATE( "datetime", 'T', sizeof(DATETIME), 0, string, &numeric, logical, date, datetime, currency); rc = MEMVAR_UPDATE( "currency", 'Y', sizeof(CURRENCY), 0, string, &numeric, logical, date, datetime, currency); }
