Set Presentation Space Service Condition

The Set Presentation Space Service Condition function sets the condition for using the following functions:

• Get Partial Presentation Space
• Find Field
• Search for String

The client application sets the condition by calling a function such as:

• Start PS position
• PS length
• EOF flag
• Search direction
• ASCIIZ string

The client must specify the Set Presentation Space Service Condition function before invoking the functions listed above. The conditions set by this function remain in effect until the next Set Presentation Space Service Condition function is called. The client sends the following message to set the condition:

PostMessage( hServerWnd,
             WM_DDE_POKE,
             hClientWnd,
             PackDDELParam(WM_DDE_POKE,
             (hData, aEPSCOND) );

where:

hData

Identifies a handle to a Windows global memory object containing:

typedef struct tagPSSERVCOND
{
  unsigned char  poke[(sizeof(DDEPOKE)-1)];
  unsigned short uPSStart;                    /* PS Position
  unsigned short uPSLength;                   /* Length of String or PS
  unsigned short uSearchDir;                  /* Direction for search
  unsigned short uEOFflag;                    /* EOF effective switch
  unsigned char  szTargetString[1];           /* Target String
} PSSERVCOND;
 
typedef union tagDDE_PSSERVCOND
{
  DDEPOKE     DDEpoke;
  PSSERVCOND  DDEcond;
} DDE_PSSERVCOND, *lpDDE_PSSERVCOND;

The following values are valid at the uSearchDir field:

 PCS_SRCHFRWD    0        /* Search forward.
 PCS_SRCHBKWD    1        /* Search backward.

The following values are valid for the uEOFflag field:

 PCS_UNEFFECTEOF 0   /* The PS Area is not truncated at End of Field (EOF).
 PCS_EFFECTEOF   1   /* The PS Area is truncated at End of Field (EOF).

If the value of uEOFflag is PCS_EFFECTEOF then the PS length and Search Direction are not used.

aEPSCOND

Identifies the item for the Set Presentation Space Service Condition function.