Accessing Files Programmer's Guide (32650-90885)

38 Chapter2

Creating A File

The HPFOPEN Intrinsic

0 Privilege level zero (most privileged level)

1 Privilege level one

2 Privilege level two

3 Privilege level three (least privileged level)

Default: 3

39/I32 Access type:

Passes a value indicating how to use the ﬁle, either sequentially or

randomly. The ﬁle system uses this information to determine the most

efﬁcient prefetching algorithm to improve the performance of the ﬁle

access.

The following values are valid:

0 Access the ﬁle sequentially

1 Access the ﬁle randomly

Default: 0

(ASC) Not used for asynchronous devices.

40/I32 Block factor:

Passes the number of logical records to be contained in one physical record

(block). This value is used to calculate the physical record size (block size)

for disk and magnetic tape ﬁles. Valid ranges are 1..32,767. This option is

applicable only at ﬁle creation.

For ﬁxed-length records, this option speciﬁes the actual number of records

in a block. For variable-length records, this option is interpreted as a

multiplier used to compute the block size (

record size option * block

factor

option

). For undeﬁned-length records, this option is always one logical

record per block.

This

itemnum

may not be speciﬁed when creating hierarchical directories.

Default: 1 for ﬁles opened NOBUF; for ﬁles opened BUF, it is calculated by

dividing the speciﬁed records into the block size conﬁgured for the device.

(ASC) Not used for asynchronous devices.

41/I32 Name syntax:

Speciﬁes which of three name semantics will be used to interpret the

ﬁlename passed to HPFOPEN:

0 MPE-escaped semantics

1 MPE-only sematics

2 POSIX semantics

MPE-escaped name semantics is the default value for this

itemnum

. The

selected name semantics do not apply to ﬁle equations speciﬁed through