Guardian Procedure Calls Reference Manual

SETSYNCINFO) and the 32-bit key items of the FILE_GETINFOLIST_, FILEINFO, and
FILERECINFO procedures.
• Format 2 key-sequenced files with increased limits not supported on legacy 514-byte sector
disks
FILE_OPEN_ does not support the open of format 2 key-sequenced files with increased limits
(in H06.28/J06.17 RVUs with specific SPRs and later RVUs) on legacy 514-byte sector disks.
The open attempt will fail with an FEINVALOP (2) error.
Terminal Considerations
The terminal being used as the operator console should not be opened with exclusive access. If it
is, console messages are not logged.
Interprocess Communication Considerations
• Maximum concurrent nowait operations for an open of $RECEIVE
The maximum number of concurrent nowait operations permitted for an open of $RECEIVE is
1. Attempting to open $RECEIVE and to specify a value greater than 1 causes an error 28 to
be returned.
• When FILE_OPEN_ completes
When process A attempts to open process B, FILE_OPEN_ completes as follows:
◦ If process B has already opened $RECEIVE with file-management system messages
disabled, the open call by process A completes immediately.
◦ If process B has opened $RECEIVE requesting file-management system messages enabled,
the open call completes when process B reads the open message from process A by using
READ[X], or if B uses READUPDATE[X], the open call completes when process B replies
to the open message (by using REPLY[X]).
If process B has not yet opened $RECEIVE, the open by process A does not complete
until process B opens $RECEIVE. Specifically, the open by process A completes as follows:
– When process B opens $RECEIVE with file-management system messages disabled,
a waited open by process A completes immediately, but a nowait open by process
A completes after the first read of $RECEIVE by process B.
– When process B opens $RECEIVE with file-management system messages enabled,
the open call by process A completes when process B reads the open message from
A by using READ[X], or if B uses READUPDATE[X], the open call completes when
process B replies to the open message (by using REPLY[X]).
• Message formats
When $RECEIVE is opened by FILE_OPEN_, system messages are delivered to the caller in
D-series format unless messages in C-series format are requested by setting options.<14>
to 1. (No file-management system messages are delivered to the caller if options.<15> is
set to 1 when opening $RECEIVE.)
• Messages from high-PIN processes
Opening $RECEIVE with FILE_OPEN_ implies that the caller is capable of handling messages
from processes with PINs greater than 255.
• Opening $RECEIVE and being opened by a remote long-named process
If a process uses the FILE_OPEN_ procedure to open $RECEIVE and requests that C-series
format messages be delivered (or if a process uses the OPEN procedure to open $RECEIVE),
then a subsequent open of that process by another process on a remote node that has a
468 Guardian Procedure Calls (F)