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

Chapter 9 267
Intrinsics Reference (cont)
HPFOPEN
Not meaningful for asynchronous devices.
Item# = 40 block factor option (I32)
Not meaningful for asynchronous devices.
Item# = 42 device class option (CA)
Passes a device class name which is used by the file
system to select a nonsharable device from a configured
list of available devices within that device class. The
name can have a length of up to eight alphanumeric
characters, beginning with a letter. If you specify a
device class, the file is allocated to any available device
in that class. Note that all character arrays must start
on a halfword boundary.
Only one of the following options can be in effect when
a file is opened:
device name option (Item# = 20),
volume class option (Item# = 22), volume name
option
(Item# = 23), device class option
(Item# = 42). The last itemnum specified takes
precedence over all previously specified
itemnums from
this group. Any duplication is flagged as a warning.
Item# = 43 UFID option (record)
Not meaningful for asynchronous devices.
Item# = 44 numbuffers option (I32)
Not meaningful for asynchronous devices. Data
transfers to and from terminals and printers are
always unbuffered.
Item# = 45 fill character option (CA)
Passes two ASCII characters that determine what
padding character you wish to use at the end of blocks
or unused pages. You must not use delimiter characters
for this option. The fill character must be a two-byte
array. The first character only is used as the padding
character. The second character is reserved for future
use. This option is applicable only at file creation. The
default is the ASCII null character. Note that all
character arrays must start on a halfword boundary.
Item# = 46 inhibit buffering option (I32)
Not meaningful for asynchronous devices.
Item# = 47 numextents option (I32)
Not meaningful for asynchronous devices.
Item# = 48 reverse VT option (I32)