Guardian Procedure Calls Reference Manual (G06.25+)

Guardian Procedure Calls (D-E)
Guardian Procedure Calls Reference Manual—522629-013
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DEVICEINFO Procedure
(Superseded by FILE_GETINFOBYNAME_
devtype output
INT:ref:1
returns the device type of the associated file in this form:
<0> Demountable
<1> Audited disk, or the file name specified was a subdevice
<2:3> Undefined
<4:9> Device type
<10:15> Device subtype
If the device type is greater than 63, bits <4:9> are set to 44. To obtain information
on devices with a device type greater than 63, call either the
FILE_GETINFOBYNAME_ or FILE_GETINFOLISTBYNAME_ procedure. Refer to
Appendix A, Device Types and Subtypes
for a list of the device types.
physical-recordlen output
INT:ref:1
returns the physical record length associated with the file. Physical record length
is determined as follows:
nondisk devices
physical-recordlen is the configured record length.
disk files
physical-recordlen is the maximum possible transfer length. The transfer
length is equal to the configured buffer size for the device (either 2048 or 4096
bytes). (For an Enscribe disk file, the logical record length can be obtained
through the FILE_GETINFO[BYNAME]_ , FILE_GETINFOLIST[BYNAME]_ , or
FILERECINFO procedure.)
processes and $RECEIVE file
a length of 132 is returned in
physical-recordlen. This is the system
convention for interprocess files.
Considerations
•
All parameters are required. If any are missing, or in error, DEVICEINFO returns
with no error indication.
•
When DEVICEINFO is called with a file name that designates a subtype 30
process, it sends a device-type inquiry system message to the process to
determine the device type and subtype. The format of this completion message is
described in the
Guardian Procedure Errors and Messages Manual.
•
A deadlock occurs if a subtype 30 process calls DEVICEINFO on its own process
name.
•
For interprocess messages directed to a process pair, file-system errors 200
(ownership) and 201 (path down) are retried automatically to the other member of
the pair.