GetRecord

Get data record with key equal to target value.

Short Name

EQLREC()

Type

ISAM function

Declaration

COUNT GetRecord(COUNT keyno, pVOID target, pVOID recptr)

Description

GetRecord() searches index file number keyno for an entry matching the key value pointed to by target. If an exact match is found, GetRecord() reads the associated data record into the buffer area pointed to by recptr, and this record becomes the current ISAM record. If no match is found or an error occurs, the current ISAM record remains unchanged.

If the associated data file has variable length records, then only the fixed-length portion, defined by dreclen in the original call to CreateIFile(), is actually read into the buffer pointed to by recptr. If you wish to read the entire variable-length record into the same or a different buffer, issue a call to ReReadVRecord() after the call to GetRecord(). Note that ReReadVRecord() requires you to specify the size of the buffer area so that it can check if sufficient space is available.

Notice that you do not directly identify the data file number involved. The IFIL structures described in “ISAM Functions” of the c-tree Plus Reference Guide contain the correspondence between the index file number (keyno) and the associated data file.

Does not support duplicate allowed (non-unique) indices if 4-byte record offset is not known. Use GetGTERecord(), or a similar function, with duplicate keys.

Return

Value	Symbolic Constant	Explanation
0	NO_ERROR	Successful retrieval of current ISAM record.
33	DNUL_ERR	recptr is NULL. No data file read performed.
42	DLOK_ERR	Could not get lock on data record. No data file read performed.
101	INOT_ERR	No match for target key value found.

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

Example

COUNT    part_idx;

TEXT     part_key[25];


struct invd {

    TEXT     delflg[4];

    LONG     part_no;

    LONG     on_hand;

    LONG     on_order;

    TEXT     part_name[60];

} recbuf;


printf("\nEnter part name: ");

scanf("%24s",part_key);


switch (GetRecord(part_idx,part_key,&recbuf)) {


case NO_ERROR:

    printf("\nParts on order for %s = %ld",

           recbuf.part_name,recbuf.on_order);

    break;


case DLOK_ERR:

    printf("\nCould not get record lock.");

    break;


case INOT_ERR:

    printf("\nPart name not on file.");

    break;


default:

    printf("\nProgramming Error (code = %d file = %d)", isam_err,isam_fil);

Limitations

No check is made to determine if recptr points to a region sufficiently large to accept a data record. If the area is too small, either code or data will be clobbered.

Does not support duplicate allowed (non-unique) indices if 4-byte record offset is not known. Use GetGTERecord(), or a similar function, with duplicate keys.