Guardian Procedure Calls Reference Manual

Table 15 FILE_ALTERLIST_ Item Codes (continued)
DescriptionSize (Bytes)Code
Note that the alteration of key-sequenced files with these increased
limits is not supported on legacy 514-byte sector disks, and the
alteration attempt will fail with an FEINVALOP (2) error.
For key-sequenced files in RVUs earlier than H06.28/J06.17, regardless
of file organization or format:
• If the alternate keys are unique, the maximum length is 253.
• If the alternate key allows duplicates and is defined as
insertion-ordered, the maximum length is 245 – primary key length.
• If the alternate keys allow normal duplicates, the maximum length
is 253 – primary-key length
For further information, see the Enscribe Programmer’s Guide.
is the number of bytes from the beginning of the record to where the
alternate-key field starts. The maximum key offset is equal to the
key-offset
(INT:1)
maximum record length minus 1 and depends on the file organization
and format.
is the relative number in the alternate-key parameter array of this key’s
alternate-key file. The first alternate-key file’s keyfilenum is 0.
key-filenum
(INT:1)
specifies a null value if attributes.<0> = 1. Note that the character
must reside in the righthand byte.
null-value
(INT:1)
During a write operation, if a null value is specified for an alternate-key
field, and the null value is encountered in all bytes of this key field, the
file system does not enter the reference to the record in the alternate-key
file. (If the file is read using this alternate-key field, records containing
a null value in this field will not be found.)
During a writeupdate operation (write-count = 0), if a null value
is specified, and the null value is encountered in all bytes of this key
field within buffer, the file system deletes the record from the primary
file but does not delete the reference to the record in the alternate file.
contains these fields:attributes
(INT:1)
means a null value is specified.= 1<0>
means the key is unique. If an attempt is made to insert a record that
duplicates an existing value in this field, the insertion is rejected with
an error 10 (duplicate record).
= 1<1>
means that automatic updating is not performed on this key.= 1<2>
means that alternate-key records with duplicate key values are ordered
by the value of the primary-key field. This attribute has meaning only
for alternate keys that allow duplicates
= 0<3>
means that alternate-key records with duplicate key values are ordered
by the sequence in which those records were inserted into the
= 1
alternate-key file. This attribute has meaning only for alternate keys
that allow duplicates.
Reserved (must be 0)<4:15>
Number of alternate-key files. The umber of files that are to hold alternate-key records. The
maximum value is 100; the default is 0. FILE_ALTERLIST_ does not automatically create the
alternate-key files.
2102
Alternate-file name-length array. An array of INT values, each giving the length in bytes of the
corresponding alternate-file name found in item 104. The length in bytes of this item is 2 times
the value of item 102.
*103
350 Guardian Procedure Calls (F)