NAME
gettune() — get the value of a kernel tunable parameter
SYNOPSIS
#include <sys/dyntune.h>
int gettune(
const char *tunable,
uint64_t *value
);
DESCRIPTION
This function retrieves the current value of the kernel tunable
parameter named
tunable.
The value is passed back through the supplied
value
pointer.
The value returned is the value for the
tunable that is being used by the currently running kernel.
RETURN VALUE
This function returns zero for success or returns -1 for an error.
ERRORS
If this function returns -1 to indicate an error, the global variable
errno
will be set to one of the following values, to indicate the error that occurred:
- EFAULT
tunable
or
value
specifies an address that is inaccessible.
- EIO
The Kernel Registry Service was unavailable or encountered an error.
- ENOENT
The specified tunable parameter does not exist.
WARNINGS
Some tunables have signed integer values.
For these tunables, the caller
must cast the returned
value
to an
int64_t
type before using it.
To find out which tunables have signed integer values,
use the
tuneinfo2()
system call
(see
tuneinfo2(2)),
or consult the tunable parameter manpages.
AUTHOR
gettune()
was developed by HP.
