SWAPON(2)                            SysV                            SWAPON(2)



NAME
     swapon - add a swap device for interleaved paging/swapping

SYNOPSIS
     swapon(special)
     char *special;

DESCRIPTION
     swapon makes the block device 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 special is calculated at the time the device
     is first made available for swapping.

ERRORS
     swapon fails if any of the following is true.

     [EACCES]         Search permission is denied for a component of the path
                      prefix.

     [EIO]            An I/O error occurred while opening the swap device.

     [EINVAL]         Disk device does not allow swapping.  Such devices
                      include the 20GB/A Optical Disk Library System, whose
                      performance characteristics are not suitable for
                      swapping.

     [ENAMETOOLONG]   A component of a pathname exceeded 255 characters, or an
                      entire pathname exceeded 1023 characters.

     [ENOENT]         The named device does not exist.

     [ENOTBLK]        special is not a block device.

     [ENOTDIR]        A component of the path prefix is not a directory.

     [ENXIO]          The major device number of special is out of range (this
                      indicates no device driver exists for the associated
                      hardware).

     [EPERM]          The caller is not the super-user.

SEE ALSO
     swapon(1M)

DIAGNOSTICS
     If an error has occurred, a value of -1 is returned and errno is set to
     indicate the error.