Guardian Procedure Calls Reference Manual

exclusion
input
INT:value
specifies the desired mode of compatibility with other openers of the file. (See General
Considerations (page 461).) Valid values are:
Shared0
Exclusive1
Process exclusive2
Protected3
The default is 0.
nowait-depth
input
INT:value
specifies whether I/O operations are to be nowait. If present and not 0, this parameter specifies
the number of nowait I/O operations that can be in progress for the file concurrently with other
processing. The maximum value is 1 for disk files and $RECEIVE. The maximum value is 15
for other objects, except for the TMF transaction pseudofile (TFILE), which has a maximum of
1000. (For details about the TFILE, see the TMF Application Programmer's Guide.) If this
parameter is omitted or 0, I/O operations are waited.
sync-or-receive-depth
input
INT:value
The purpose of this parameter depends on the type of device being opened:
specifies the number of nonretryable (that is, write) requests whose completion the file system must
remember. A value of 1 or greater must be specified to recover from a path failure occurring during
disk file
a write operation. This value also implies the number of write operations that the primary process
in a process pair can perform to this file without intervening checkpoints to its backup process. For
disk files, this parameter is called sync depth. The maximum value is 15.
If omitted, or if 0 is specified, internal checkpointing does not occur. Disk path failures are not
automatically retried by the file system.
specifies the maximum number of incoming messages read by READUPDATE[X] that the application
process is allowed to queue before corresponding reply operations must be performed.
$RECEIVE file
If omitted or 0, READUPDATE[X] and reply operations to $RECEIVE are not permitted.
For $RECEIVE, this parameter is called receive-depth, and the maximum number of queued incoming
messages is 4047 in the H06.17/J06.06 and earlier RVUs. From the H06.18/J06.07 RVU onwards,
the maximum receive-depth value has been increased from 4047 to 16300.
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.
process pair
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
FILE_OPEN_ Procedure 459