FairCom ISAM for C

ResetRecord

Updates the current ISAM record image buffers.

Short Name

UPDCURI()

Type

ISAM function

Declaration

COUNT ResetRecord(COUNT datno, COUNT mode);

Description

ResetRecord() manipulates the internal image of the current ISAM record kept by c-tree. An image is kept of the current ISAM record’s key structure and the current ISAM record’s file address. Whenever an ISAM function changes the current ISAM record, such as an AddRecord() or ReWriteRecord(), the original current ISAM record information is copied over to a secondary buffer before the primary buffer is changed. ResetRecord() can be used to manage these two buffers.

datno specifies the ISAM file that is to be affected.

mode can be one of several values;

mode	Description
SWTCURI	Switches the ISAM buffers. Use SWTCURI after a rewrite to move the old buffer back to the original. This allows you to keep your position in the file as it was before the rewrite.
SAVCURI	Copies the current ISAM record information to the secondary buffer.
RSTCURI	Restores the primary ISAM record information from the secondary area.

Return

Value	Symbolic Constant	Explanation
22	FNUM_ERR	File number is out of range.
26	FACS_ERR	File number is not assigned to a file in use.
47	FINT_ERR	c-tree has not been initialized.
48	FMOD_ERR	datno is not assigned to a data file.
116	IMOD_ERR	Invalid value in mode.

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

Example

COUNT invfil;

struct invd {

TEXT delflg[4];

LONG part_no;

LONG on_hand;

TEXT part_name[60];

} recbuf;

scanf("%ld %59s %ld",&recbuf.part_no,recbuf.part_name, &recbuf.on_hand);

recbuf.delflg = '\0'; /* clear delete flag */

if (AddRecord(invfil,&recbuf) )

printf("\nAddRecord error %d in file %d", isam_err, isam_fil);

/* after adding record, restore current ISAM to previous point */

if (ResetRecord(invfil,SWTCURI) )

printf("\nCannot reset, error %d",isam_err);