fs_symlinks.5 (2010 09)

f
fs_symlinks(5) fs_symlinks(5)
(Tunable Kernel Parameters)
NAME
fs_symlinks - maximum number of symbolic links used to resolve a path name
VALUES
Failsafe
20
Default
20
Allowed values
The minimum value allowed is 20. The maximum value allowed is 1024, or 1K.
Specify a positive integer value.
DESCRIPTION
The fs_symlinks tunable represents the maximum number of symbolic links followed by the kernel
when resolving a path name. Applications that create symbolic links and/or parse path names should
also now use this limit represented by fs_symlinks
to be consistent with the kernel.
Who Is Expected to Change This Tunable?
Anyone expecting to run applications using path names that may expand to a large number of symbolic
links.
Restrictions on Changing
None. The
fs_symlinks tunable is dynamic (tuning will take effect immediately on the running sys-
tem).
When Should the Value of This Tunable Be Raised?
This tunable value should be raised when applications are expected to create and/or parse path names
that may expand to a large number of symbolic links.
What are the Side Effects of Raising the Value?
None.
When Should the Value of This Tunable Be Lowered?
This value rarely needs to be lowered, unless there is a reason to limit the number of symbolic links in an
expanded path name.
What are the Side Effects of Lowering the Value?
The kernel will not be able to resolve path names with more symbolic links than the limit represented by
fs_symlinks.
What Other Tunable Values Should Be Changed at the Same Time?
None.
WARNINGS
All HP-UX kernel tunable parameters are release specific. This parameter may be removed or have its
meaning changed in future releases of HP-UX.
NOTE: The define
MAXSYMLINKS, traditionally defined in <sys/param.h>
, is now obsolete and
should not be used. This limit (number of symbolics links that may be expanded in a path name) is now
available to applications via this new tunable parameter,
fs_symlinks. The interfaces provided by the
tunable infrastructure should be used to obtain the value of fs_symlinks. At the application level, use
the gettune (2) or kctune (1M) interface. Applications using the MAXSYMLINKS define may not be con-
sistent with the kernel. The MAXSYMLINKS define will be removed in post-HP-UX 11i Version 2
releases.
Installation of optional kernel software, from HP or other vendors, may cause changes to tunable parame-
ter values. After installation, some tunable parameters may no longer be at the default or recommended
values. For information about the effects of installation on tunable values, consult the documentation for
the kernel software being installed. For information about optional kernel software that was factory
installed on your system, see HP-UX Release Notes at
http://www.hp.com/go/hpux-core-docs.
HP-UX 11i Version 3: September 2010 − 1 − Hewlett-Packard Company 1