Guardian Procedure Calls Reference Manual (G06.25+)

Guardian Procedure Calls (F)
Guardian Procedure Calls Reference Manual—522629-013
5-117
FILE_OPEN_ Procedure
that the meaning of this flag is opposite from that of the equivalent flag
in the OPEN procedure). For other device types, this bit must be 0.
options (continued)
When options is omitted, 0 is used.
seq-block-buffer-id input
INT:value
if present and not 0, identifies the buffer to be used for shared sequential block
buffering; all opens made through FILE_OPEN_ and using this ID share the same
buffer. Any integer value can be supplied for this parameter.
If
seq-block-buffer-id is omitted or 0, and sequential block buffering is
requested, the buffer is not shared. In this case, the buffer resides in the process’s
process file segment (PFS) with the size given by
seq-block-buffer-len.
seq-block-buffer-len input
INT:value
specifies whether sequential block buffering is being requested. If this parameter
is supplied with a value greater than 0, it indicates a request for sequential block
buffering and specifies the length in bytes of the sequential block buffer. If this
parameter is omitted or 0, sequential block buffering is not requested. Sequential
block buffering is only for disk files.
If this value is less than the data-block length that was given to this file or to any
associated alternate-key file, the larger value is used. Supplying a nonzero value
for this parameter causes a buffer to be allocated unless an existing buffer is to be
shared (see the
seq-block-buffer-id parameter). If an existing buffer is to be
shared, but it is smaller than
seq-block-buffer-len, sequential block buffering
is not provided and a warning value of 5 is returned.
primary-processhandle input
INT .EXT:ref:10
indicates that the caller is requesting a backup open and specifies the process
handle of the primary process that already has the file open when its backup
attempts to open the file. If this parameter is supplied and not null (a null process
handle has -1 in each word),
filenum must contain the filenum value that was
returned to the primary. If a null process handle is supplied, or the parameter is
omitted, a normal open is being requested.
This option is used only when the backup process is the caller. It is more common
for the primary to perform this operation by a call to FILE_OPEN_CHKPT_.