FairCom ISAM for C

PositionVSet

Establish current variable-length ISAM record as current position in set.

Short Name

MIDVSET()

Type

ISAM function

Declaration

COUNT PositionVSet(FILNO keyno, pVOID recptr, COUNT siglen, pVRLEN plen)

Description

In V12 the file number typedef was formally changed from COUNT, a two-byte value to FILNO, a four-byte value. Refer to this link for compatibility details. Four Byte File Numbering

PositionVSet() is the same as its fixed-length counter-part, PositionSet(), except that one argument has been added: plen.

plen acts as both an input and output parameter:

On input, plen contains the length of the output buffer.
On output, the contents of plen is the actual data-record length. If the length of the output buffer is less than the actual record length, a partial read is performed. If an error occurs, plen is unspecified.

Read the function description for PositionSet() for additional important information.

Return

Value	Symbolic Constant	Explanation
0	NO_ERROR	Successful retrieval of current ISAM record.
633	NPLN_ERR	plen is NULL. No data file read performed.
634	NLEN_ERR	*plen negative on input.

See c-tree Error Codes for a complete listing of valid c-tree error values.