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.\" @(#)swapon.2 6.7 (Berkeley) 3/10/91
.Nd add a swap device for interleaved paging/swapping
.Fn swapon "const char *special"
available to the system for
allocation for paging and swapping. The names of potentially
available devices are known to the system and defined at system
configuration time. The size of the swap area on
is calculated at the time the device is first made available
If an error has occurred, a value of -1 is returned and
is set to indicate the error.
.Bl -tag -width ENAMETOOLONG
A component of the path prefix is not a directory.
The pathname contains a character with the high-order bit set.
A component of a pathname exceeded 255 characters,
or an entire path name exceeded 1023 characters.
The named device does not exist.
Search permission is denied for a component of the path prefix.
Too many symbolic links were encountered in translating the pathname.
The caller is not the super-user.
been made available for swapping
configured into the system as a swap device.
The major device number of
is out of range (this indicates no device driver exists
for the associated hardware).
An I/O error occurred while opening the swap device.
points outside the process's allocated address space.
There is no way to stop swapping on a disk so that the pack may be
This call will be upgraded in future versions of the system.
function call appeared in