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@(#)swapon.2 8.1 (Berkeley) 6/4/93
.Dd June 4, 1993 .Dt SWAPON 3 .Os .Sh NAME .Nm swapon .Nd add a swap device for interleaved paging/swapping .Sh SYNOPSIS n unistd.h .Ft int .Fn swapon "const char *special" .Sh DESCRIPTION f -symbolic This interface is available from the compatibility library, libcompat and
This interface is provided for compatibility only and has been obsoleted by .Xr swapctl 2 . .Ef
p .Fn swapon makes the block device .Fa 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 .Fa special is calculated at the time the device is first made available for swapping. .Sh RETURN VALUES If an error has occurred, a value of -1 is returned and .Va errno is set to indicate the error. .Sh ERRORS .Fn swapon succeeds unless: l -tag -width ENAMETOOLONG t Bq Er ENOTDIR A component of the path prefix is not a directory. t Bq Er ENAMETOOLONG A component of a pathname exceeded rq Dv NAME_MAX characters, or an entire path name exceeded rq Dv PATH_MAX characters. t Bq Er ENOENT The named device does not exist. t Bq Er EACCES Search permission is denied for a component of the path prefix. t Bq Er ELOOP Too many symbolic links were encountered in translating the pathname. t Bq Er EPERM The caller is not the super-user. t Bq Er ENOTBLK .Fa special is not a block device. t Bq Er EBUSY The device specified by .Fa special has already been made available for swapping t Bq Er EINVAL The device configured by .Fa special was not configured into the system as a swap device. t Bq Er ENXIO The major device number of .Fa special is out of range (this indicates no device driver exists for the associated hardware). t Bq Er EIO An I/O error occurred while opening the swap device. t Bq Er EFAULT .Fa special points outside the process's allocated address space. .El .Sh SEE ALSO .Xr swapctl 2 , .Xr swapctl 8 , .Xr swapon 8 .Sh HISTORY The .Fn swapon function call appeared in x 4.0 and was removed .Nx 1.3 .Sh BUGS This call will be upgraded in future versions of the system.
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