minix/external/public-domain/sqlite/man/SQLITE_IOCAP_ATOMIC.3
2018-11-18 02:11:42 +00:00

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.Dd March 11, 2017
.Dt SQLITE_IOCAP_ATOMIC 3
.Os
.Sh NAME
.Nm SQLITE_IOCAP_ATOMIC ,
.Nm SQLITE_IOCAP_ATOMIC512 ,
.Nm SQLITE_IOCAP_ATOMIC1K ,
.Nm SQLITE_IOCAP_ATOMIC2K ,
.Nm SQLITE_IOCAP_ATOMIC4K ,
.Nm SQLITE_IOCAP_ATOMIC8K ,
.Nm SQLITE_IOCAP_ATOMIC16K ,
.Nm SQLITE_IOCAP_ATOMIC32K ,
.Nm SQLITE_IOCAP_ATOMIC64K ,
.Nm SQLITE_IOCAP_SAFE_APPEND ,
.Nm SQLITE_IOCAP_SEQUENTIAL ,
.Nm SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN ,
.Nm SQLITE_IOCAP_POWERSAFE_OVERWRITE ,
.Nm SQLITE_IOCAP_IMMUTABLE
.Nd Device Characteristics
.Sh SYNOPSIS
.Fd #define SQLITE_IOCAP_ATOMIC
.Fd #define SQLITE_IOCAP_ATOMIC512
.Fd #define SQLITE_IOCAP_ATOMIC1K
.Fd #define SQLITE_IOCAP_ATOMIC2K
.Fd #define SQLITE_IOCAP_ATOMIC4K
.Fd #define SQLITE_IOCAP_ATOMIC8K
.Fd #define SQLITE_IOCAP_ATOMIC16K
.Fd #define SQLITE_IOCAP_ATOMIC32K
.Fd #define SQLITE_IOCAP_ATOMIC64K
.Fd #define SQLITE_IOCAP_SAFE_APPEND
.Fd #define SQLITE_IOCAP_SEQUENTIAL
.Fd #define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN
.Fd #define SQLITE_IOCAP_POWERSAFE_OVERWRITE
.Fd #define SQLITE_IOCAP_IMMUTABLE
.Sh DESCRIPTION
The xDeviceCharacteristics method of the sqlite3_io_methods
object returns an integer which is a vector of these bit values expressing
I/O characteristics of the mass storage device that holds the file
that the sqlite3_io_methods refers to.
.Pp
The SQLITE_IOCAP_ATOMIC property means that all writes of any size
are atomic.
The SQLITE_IOCAP_ATOMICnnn values mean that writes of blocks that are
nnn bytes in size and are aligned to an address which is an integer
multiple of nnn are atomic.
The SQLITE_IOCAP_SAFE_APPEND value means that when data is appended
to a file, the data is appended first then the size of the file is
extended, never the other way around.
The SQLITE_IOCAP_SEQUENTIAL property means that information is written
to disk in the same order as calls to xWrite().
The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that after reboot
following a crash or power loss, the only bytes in a file that were
written at the application level might have changed and that adjacent
bytes, even bytes within the same sector are guaranteed to be unchanged.
The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN flag indicates that a file cannot
be deleted when open.
The SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on read-only
media and cannot be changed even by processes with elevated privileges.
.Sh SEE ALSO
.Xr sqlite3_io_methods 3