Asynchronous Serial Communications Programmer's Reference Manual (32022-90052)

244 Chapter9
Intrinsics Reference (cont)
FOPEN
If aoptions are not specified, the value of all bits is
assumed to be 0.
Bits (12:4)—Access type aoptions .
=0000 Read access only.
=0001 Write access only.
=0010 Write access only, but previous data in
file not deleted.
=0011 Append access only.
=0100 Input/output access.
=0101 Update access.
=0110 Execute access.
The type of access allowed users of the file. Table 9-2
summarizes how these settings apply to terminals and
printers.
Bit (11:1)—Multirecord
aoption .
Specifies whether or not a block of data (size specified
in the tcount parameter of the read or write request)
that exceeds the file’s physical record size may be
transmitted as several records. This option is only
available for terminals. Data written to printers is not
broken up on record boundaries. Instead it is written as
a single long record.
=0 Select non-multirecord mode
(NOMULTI).
=1 Select multirecord mode (MULTI).
Bit (10:1)—Dynamic locking
aoption .
Meaningless for asynchronous devices. If specified for
files not residing on disk, this option will be ignored.
Bit (8:2)—Exclusive access
aoption .
Specifies whether you have continuous exclusive access
to this file. This option does not apply to printers.
Exclusive access is available during the first FOPEN
issued against a terminal. If a session is already
running on a terminal, it is not possible to issue
another FOPEN with “exclusive” specified. (See the
MPE/iX Intrinsics Reference Manual for more
information on what each of the bit settings implies.)
=00 Default.
=01 Exclusive access.