ENABLE Reference Manual

THE GENERAL SERVER
General Server Requirements
GENERAL SERVER REQUIREMENTS
You can use the General Server with requester programs that you
have written. These programs must conform to the external
specifications detailed in the following paragraphs.
Opening the General Server
You can open the General Server with a nowait depth of 0 or 1
and a sync depth of 0 or 1. The sync depth mechanism of the
General Server emulates that of the disc process in that only
replies to nonretryable requests are saved for retransmission.
UPDATE, DELETE, and INSERT are nonretryable operations; OPEN and
READ operations get reexecuted, regardless of sync ID. If a
request for a nonretryable operation arrives with a sync ID older
than the one saved by the General Server for that requester, the
General Server responds with GUARDIAN file error 39.
General Server Request Format
General Server requests consist of a fixed prefix common to all
types of transactions and a variable portion dependent upon the
transaction code (TRANS-CODE) entry. The request prefix consists
of a 24-byte PATHWAY header, a 54-byte General Server header, and
a 96-byte context buffer. Figure E-1 shows a DDL structure that
describes the format of the General Server request prefix.
Table E-1 lists the valid values for the TRANS-CODE field and the
types of transactions to which these values apply.
E-6