Technical data

Table 2–5: Case-Sensitivity Differences
OpenVMS (ODS-2)
UNIX
Stores everything in uppercase. For
example, any case variations of the
following file name is stored in uppercase:
CHAPTER_ONE.TXT;1
Regards uppercase and lowercase
characters as different characters.
For example, on a UNIX system, the
following file names represent three
different files:
• CHAPTER_ONE.TXT
• Chapter_One.Txt
• chapter_one.txt
2.2.6 File Types
Table 2–6 describes the file type differences between OpenVMS and UNIX.
Table 2–6: File Type Differences
OpenVMS
UNIX
Important in OpenVMS file identification
Thefiletypeusuallydescribesthekindof
data in the file.
UNIX systems do not use file types.
However, UNIX has certain naming
conventions that resemble OpenVMS file
types.
For example, a text file typically has a file
type of .TXT.
All OpenVMS directories have a file type
of .DIR.
For example, file names ending in
txt
are
text files.
UNIX directories do not have file types.
2.2.7 Version Numbers
Table 2–7 describes file version number differences between OpenVMS and UNIX.
Table 2–7: Version Number Differences
OpenVMS
UNIX
Every file has a version number.
When a file is created, the system assigns it
a version number of 1. Subsequently, when
a file is edited or when subsequent versions
of that file are created, the version number
automatically increases by 1. Therefore,
many versions of a file with the same file
namecanexistinthesamedirectory.
The UNIX file system does not support
automatic creation of multiple versions.
In most cases, if you edit a UNIX file, the
system saves only the most recently edited
copy.
For example:
FILE_NAME.TXT;1
FILE_NAME.TXT;2
FILE_NAME.TXT;3
For example:
file_name.txt
2.2.8 Linking Files
A link is a directory entry that refers to a file or another directory. Table 2–8
describes the differences between OpenVMS and UNIX file linking.
Understanding OpenVMS and UNIX Implementations 2–7