HP 3000 Manuals HP 3000 Manuals
Using Symbolic Links
You have a lot of flexibility in naming directories and files by using
symbolic links. What if you want to move a set of files from one
location to another without affecting the normal processing of any
application that accesses those files. To do this, you can move the
actual files to the new location, and in the old location create symbolic
links with the same name specifying the new location of the files.
Creating symbolic links
Suppose that files file1, file2, and file3 originally existed under the
MPE group PXGROUP of account DEVELOP. You have decided to link the files
to the /users/denis/bin/FILES directory. To ensure that all of the
applications that access those files will still function properly, you
can create symbolic links to those files in the old directory
/DEVELOP/PXGROUP.
Use the NEWLINK command to create the symbolic links.
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| |
| |
| :rename ./file1, /users/denis/bin/FILES/file1 |
| :rename ./file2, /users/denis/bin/FILES/file2 |
| :rename ./file3, /users/denis/bin/FILES/file3 |
| :chdir /DEVELOP/PXGROUP |
| :newlink ./file1, /users/denis/bin/FILES/file1 |
| :newlink ./file2, /users/denis/bin/FILES/file2 |
| :newlink ./file3, /users/denis/bin/FILES/file3 |
| |
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From this point on, anytime an application accesses these files by their
old names, the symbolic links will redirect the file system to the new
location of the files.
NOTE This only applies to commands that operate on the target of the
links and not the links themselves. For example, PURGELINK and
STORE operate on the link itself and not the target files.
You can use this method to install newer versions of these files in
another location without overlaying their current version, and changing
the symbolic links to point to the newer version. If at any time you
need to access the old version, you can point the symbolic links to that
version of the files.
Deleting symbolic links
Use the PURGELINK command to delete a symbolic link.
:purgelink ./file1, /users/denis/bin/FILES/file1
The above example removes the symbolic link file file1 in the CWD.
Renaming symbolic links
Symbolic links can be renamed by calling the POSIX C-library function
rename().
The MPE/iX RENAME command does not rename the symbolic link itself, it
renames the file pointed to by the symbolic link. You can use the
shell's MV command to rename a link.
Archiving symbolic links
Symbolic links can be stored and restored to your MPE/iX system by using
the MPE/iX STORE and RESTORE commands like any other file on the system.