The Create a Directory routine creates a directory or
subdirectory.
Format
LIB$CREATE_DIR device-directory-spec [,owner-UIC]
[,protection-enable] [,protection-value]
[,maximum-versions] [,relative-volume-number]
[,initial-allocation]
1 – Returns
OpenVMS usage:cond_value
type: longword (unsigned)
access: write only
mechanism: by value
2 – Arguments
device-directory-spec
OpenVMS usage:device_name
type: character string
access: read only
mechanism: by descriptor
Directory specification of the directory or subdirectory that
LIB$CREATE_DIR will create. The device-directory-spec argument
is the address of a descriptor pointing to this directory
specification.
The format of the device-directory-spec string conforms
to standard OpenVMS Record Management Services (RMS)
format. This specification must contain a directory or
subdirectory specification. It may contain a disk specification.
SMD$:[THIS.IS.IT] is an example of a standard RMS file
specification, where SMD$ is the disk specification and
[THIS.IS.IT] is the subdirectory specification.
This specification cannot contain a node name, file name, file
type, file version, or wildcard characters. The maximum size
of this string is 255 characters on VAX, and 4095 characters on
Alpha.
owner-UIC
OpenVMS usage:uic
type: longword (unsigned)
access: read only
mechanism: by reference
User identification code (UIC) identifying the owner of the
created directory or subdirectory. The owner-UIC argument is the
address of an unsigned longword that contains the UIC. If owner-
UIC is zero, the owner UIC is that of the parent directory. The
specified value for owner-UIC is interpreted as a 32-bit octal
number, with two 16-bit fields:
bits 00-15 - Member number
bits 16-31 - Group number
This is an optional argument. The default is the UIC of the
current process except when the directory is in UIC format. For
a directory in UIC format, for example [123,321], the UIC of the
created directory is used.
protection-enable
OpenVMS usage:mask_word
type: word (unsigned)
access: read only
mechanism: by reference
Mask specifying the bits of protection-value to be set. The
protection-enable argument is the address of an unsigned word
containing this protection mask.
The following diagram shows the structure of a protection mask.
Access is allowed for bits set to 0.
World Group Owner System
+_______________+_______________+_______________+_______________+
| D | W | E | R | D | W | E | R | D | W | E | R | D | W | E | R |
_________________________________________________________________
15 0
Bits set in the protection-enable mask cause corresponding bits
of protection-value to be set. Bits not set in the protection-
enable mask cause corresponding bits of protection-value to take
the value of the corresponding bit in the parent directory's
file protection. Bits in the parent directory's file protection
that indicate delete access do not cause corresponding bits of
protection-value to be set, however.
Following is an example of how the protection-value protection
mask is defined:
Hexadecimal
Mask Name Number Value
Protection %XDBFF S:None, O:None, G:E, W:W
enable
Parent %X13FF S:RWED, O:RWED, G:RW, W:R
directory
Protection %X37FF S:RWE, O:RWE, G:RWE, W:RW
value
The protection-enable argument is optional. It should be
used only when you want to change protection values from the
parent directory's default file protection. The default for
protection-enable is a mask of all zero bits, which results in
the propagation of the parent directory's file protection. If
the protection-enable mask contains zeros, protection-value is
ignored.
protection-value
OpenVMS usage:file_protection
type: word (unsigned)
access: read only
mechanism: by reference
System/Owner/Group/World protection value of the directory you
are creating. The protection-value argument is the address of an
unsigned word that contains this protection mask.
The bits of protection-value are set or cleared in the method
described in the definition of protection-enable above.
The protection-value argument is optional. The default is a word
of all zero bits, which specifies full access for all access
categories. Typically, protection-value is not omitted unless
protection-enable is also omitted. If protection-enable is
omitted, protection-value is ignored.
maximum-versions
OpenVMS usage:word_unsigned
type: word (unsigned)
access: read only
mechanism: by reference
Maximum number of versions allowed for files created in the newly
created directories. The maximum-versions argument is the address
of an unsigned word containing the value of the maximum number of
versions.
The maximum-versions argument is optional. The default is the
parent directory's default version limit. If maximum-versions is
zero, the maximum number of versions is not limited.
relative-volume-number
OpenVMS usage:word_unsigned
type: word (unsigned)
access: read only
mechanism: by reference
Relative volume number within a volume set on which the directory
or subdirectory is created. The relative-volume-number argument
is the address of an unsigned word containing the relative volume
number. The relative-volume-number argument is optional. The
default is arbitrary placement within the volume set.
initial-allocation
OpenVMS usage:longword_unsigned
type: longword (unsigned)
access: read only
mechanism: by reference
Initial number of blocks to be allocated to the directory. This
argument is useful for creating large directories, for example
MAIL.DIR;1. It can improve performance by avoiding the need for
later dynamic expansion of the directory.
The initial-allocation argument applies only to Files-11 Level 2
volumes; it is ignored for other volumes.
This argument is the address of an unsigned longword that
contains the initial number of blocks to be allocated to the
directory.
The initial-allocation argument is optional. The default
allocation is 1 block.