Guardian Procedure Calls Reference Manual (G06.25+)

Guardian Procedure Calls (O)
Guardian Procedure Calls Reference Manual—522629-013
11-16
OPEN Procedure (Superseded by FILE_OPEN_
Procedure )
process pair
specifies whether or not an I/O operation is automatically redirected to
the backup process if the primary process or its processor module fails.
For processes, this parameter is called sync depth. The maximum
value is determined by the process. The value must be at least 1 for
an I/O operation to a remote process pair to recover from a network
failure.
If this parameter >= 1, the server is expected to save or be able to
regenerate that number of replies.
If this parameter = 0, and if an I/O operation cannot be performed to
the primary process of a process pair, an error indication is returned to
the originator of the message. On a subsequent I/O operation, the file
system redirects the request to the backup process.
For other device types, the meaning of this parameter depends on whether the
sync-ID mechanism is supported by the device being opened. If the device does
not support the sync-ID mechanism, 0 is used regardless of what you specify (this
is the most common case). If the device supports the sync-ID mechanism,
specifying a nonzero value causes the results of that number of operations to be
saved; in case of failures, the operations can be retried if necessary.
The actual value being used can be obtained by a call to FILE_GETINFOLIST_ or
FILEINFO.
primary-filenum input
INT:value
is the file number returned to the primary process when it opened this file.
primary-filenum must be passed as -filenum.
primary-filenum and primary-process-id are supplied only if the open is
by the backup process of a process pair, the file is currently open by the primary
process,
and the checkpointing facility is not used. Both parameters must be
supplied.
A negative file number indicates that the same file number should be returned in
the backup as was returned in the primary. If a negative file number is specified
and the file number is already open by the backup process, OPEN returns file-
system error 12. In this situation, a process pair would indicate externally that
error 12 (file in use) exists when, in fact, the file is not in use by the normal
definition (open by another process in exclusive mode).
primary-process-id input
INT:ref:4
is an array that contains the 4-word
process-id of the corresponding primary
process.