The file reference can be either in MPE/iX or POSIX namespace.
The MPE file domain consists of MPE accounts, MPE groups and files which reside
in these groups.accounts. The MPE file domain is a 3 level
Hierarchical File System (HFS).
The POSIX file domain is considered a superset of the MPE file domain.
The POSIX file domain consists of a root (/) and POSIX directories,
which can contain additional directories or files. The POSIX file
domain is a multi-level Hierarchical File System.
POSIX is implemented on MPE/iX in such a manor that it is
a superset of MPE. MPE accounts are now under
the POSIX root (/) and are treated as special directories;
likewise MPE groups are located under accounts and again are treated
as special directories.
As a result of this implementation, files in the MPE file
domain can be accessed by MPE applications; and, since the POSIX
file domain is a superset of the MPE file domain,
POSIX applications can also access these files. In general MPE applications
cannot access files in the POSIX file domain unless the application,
or the file procedures it calls, are specifically coded to do so.
If the file reference does not begin with a dot or a slash, it is parsed
according to the MPE/iX syntax and has the following format:
filename [/lockword] [.groupname [.acctname]]
MPE/iX names must contain from one to eight alphanumeric characters, beginning
with an alphabetic character. If acctname is specified, you
must create directory (CD) access to the target group in the account. The
default groupname and acctname are the logon
group and account. Filenames in MPE name space are not case sensitive, and are
all shifted to uppercase.
If the file reference begins with a dot (.) or a slash (/),
it is parsed according to the POSIX syntax. In this case the file
reference can be ./Directory 1/Directory 2/Directory 3/... .
The following syntax rules apply:
File names are not shifted to uppercase.
File names can be up to 254 characters in length for absolute
pathnames, and 253 characters for relative pathnames.
File names can begin with, and contain, any of the following
characters:
a—z A—Z, 0—9, _, .
File names can contain (but not begin with) a dash (-).
File names are of the form (path/filename) where the
path/filename combination can have a maximum of 255
characters.
For more information, refer to the New Features of MPE/iX: Using
The Hierarchical File System Reference Manual for accepted
syntax of file names and directories.
Sample File Name
MPE File Name Space
POSIX File Name Space
FILENAME
FILENAME
FILENAME
filename
FILENAME
filename
longfilename
Invalid MPE file name
longfilename
Read_Me
Invalid MPE file name
Read_Me
NOTE: The file identifiers "./FILENAME" and "./filename" refer to two
different files in the POSIX name space since character case is accepted in the
POSIX name space.
Example 1:
Files in the MPE file domain in PUB.SYS (MPE syntax) are also viewed
as being a part of the POSIX file domain in /SYS/PUB/ (POSIX syntax).
NOTE: The MPE listf command executes against files in the MPE
file domain. The MPE command listfile created for POSIX executes against
files in both the MPE and POSIX file domains.