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swapon(8) [bsd man page]

SWAPON(8)						      System Manager's Manual							 SWAPON(8)

NAME
swapon - specify additional device for paging and swapping SYNOPSIS
swapon -a swapon name ... DESCRIPTION
Swapon is used to specify additional devices on which paging and swapping are to take place. The system begins by swapping and paging on only a single device so that only one disk is required at bootstrap time. Calls to swapon normally occur in the system multi-user initial- ization file /etc/rc making all swap devices available, so that the paging and swapping activity is interleaved across several devices. Normally, the -a argument is given, causing all devices marked as ``sw'' swap devices in /etc/fstab to be made available. The second form gives individual block devices as given in the system swap configuration table. The call makes only this space available to the system for swap allocation. SEE ALSO
swapon(2), init(8) FILES
/dev/[ru][pk]?b normal paging devices BUGS
There is no way to stop paging and swapping on a device. It is therefore not possible to make use of devices which may be dismounted dur- ing system operation. swapon is not implemented in 2.11BSD. 4th Berkeley Distribution November 17, 1996 SWAPON(8)

Check Out this Related Man Page

SWAPON(2)							System Calls Manual							 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. RETURN VALUE
If an error has occurred, a value of -1 is returned and errno is set to indicate the error. ERRORS
Swapon succeeds unless: [ENOTDIR] A component of the path prefix is not a directory. [EINVAL] The pathname contains a character with the high-order bit set. [ENAMETOOLONG] A component of a pathname exceeded 255 characters, or an entire path name exceeded 1023 characters. [ENOENT] The named device does not exist. [EACCES] Search permission is denied for a component of the path prefix. [ELOOP] Too many symbolic links were encountered in translating the pathname. [EPERM] The caller is not the super-user. [ENOTBLK] Special is not a block device. [EBUSY] The device specified by special has already been made available for swapping [EINVAL] The device configured by special was not configured into the system as a swap device. [ENXIO] The major device number of special is out of range (this indicates no device driver exists for the associated hardware). [EIO] An I/O error occurred while opening the swap device. [EFAULT] Special points outside the process's allocated address space. SEE ALSO
swapon(8), config(8) BUGS
There is no way to stop swapping on a disk so that the pack may be dismounted. This call will be upgraded in future versions of the system. 4th Berkeley Distribution March 9, 1986 SWAPON(2)

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