The File Set Position function repositions the media of an open file. The structure follows:
typedef struct _pmPosData { pmUInt32 Length; char *Data; } pmPos_t; typedef struct _pmiPos { char EyeCatcher[pmiMAX_EC_LEN];/* Struct eyecatcher string */ pmUInt32 StructLength; /* Length of this structure */ void *FIData; pmPos_t Position; } pmiPos_t;
where the following is true:
Parameter | Field | Description |
---|---|---|
EyeCatcher | input | Structure description string, such as pmSetParms. |
StructLength | input | Total structure length, including the EyeCatcher string. |
FIData | input | Value provided by the Access Module in response to a previous open request call. |
Position | input | A two-field structure as follows:
|
Return Codes
Usage Notes
Consider the following requirements when specifying File Set Position parameters:
- Requirement – A File Set Position function is required when the Reqtype field of the pmiCmdBlock_t structure is pmiPIDMOptSetPos.
- Data Return – An Access Module must return the same block of data after a File Set Position request as is returned before the corresponding File Get Position request.