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.Dd February 19, 2011
.Dt LIBISCSI 3
.Os
.Sh NAME
.Nm libiscsi
.Nd iSCSI network storage protocol implementation
.Sh LIBRARY
.Lb libiscsi
.Sh SYNOPSIS
.In iscsi.h
.Ft int
.Fo iscsi_target_set_defaults
.Fa "iscsi_target_t *target"
.Fc
.Ft int
.Fo iscsi_target_start
.Fa "iscsi_target_t *target"
.Fc
.Ft int
.Fo iscsi_target_listen
.Fa "iscsi_target_t *target"
.Fc
.Ft int
.Fo iscsi_target_shutdown
.Fa "iscsi_target_t *target"
.Fc
.Ft void
.Fo iscsi_target_write_pidfile
.Fa "const char *filename"
.Fc
.Ft int
.Fo iscsi_target_setvar
.Fa "iscsi_target_t *target" "const char *name" "const char *value"
.Fc
.Ft char *
.Fo iscsi_target_getvar
.Fa "iscsi_target_t *target" "const char *name"
.Fc
.Ft int
.Fo iscsi_initiator_set_defaults
.Fa "iscsi_initiator_t *initiator"
.Fc
.Ft int
.Fo iscsi_initiator_start
.Fa "iscsi_initiator_t *initiator"
.Fc
.Ft int
.Fo iscsi_initiator_discover
.Fa "iscsi_initiator_t *initiator" "char *x" "uint64_t a" "int b"
.Fc
.Ft int
.Fo iscsi_initiator_shutdown
.Fa "iscsi_initiator_t *initiator"
.Fc
.Ft int
.Fo iscsi_initiator_setvar
.Fa "iscsi_initiator_t *initiator" "const char *name" "const char *value"
.Fc
.Ft char *
.Fo iscsi_initiator_getvar
.Fa "iscsi_initiator_t *initiator" "const char *name"
.Fc
.Sh DESCRIPTION
.Nm
is a library interface to the iSCSI target and initiator.
This conforms to IETF RFC 3720.
The corresponding command line utilities for
.Nm
are
.Xr iscsi-initiator 8
and
.Xr iscsi-target 8 .
.Pp
In normal operation, a process acting as
a target (i.e. presenting storage to the network)
will call
.Fn iscsi_target_set_defaults
and will then set various values using the
.Fn iscsi_target_setvar
function.
The value of a variable can be retrieved
at any time using the
.Fn iscsi_target_getvar
function.
When all of the variables have been set,
the
.Fn iscsi_target_start
function is called, and the block storage will be
served up by the process.
.Pp
A useful illustration of the use of these functions
can be found in the source code to the
.Xr iscsi-target 8
utility.
.Pp
The
.Nm
library also provides an implementation of the client
end of the iSCSI subsystem, which is known as the
initiator.
The process acting as an initiator will first call the
.Fn iscsi_initiator_set_defaults
function, to set default values for the initiator variables.
Once all the values have been set to the user preferences
using the
.Fn iscsi_initiator_setvar
function, then the
.Fn iscsi_initiator_start
function is called.
.Pp
The
.Nm
library can be used to perform iSCSI device discovery
by calling the
.Fn iscsi_initiator_discovery
function.
This will return a list of all the iSCSI targets which
are serving up block storage according to the variables
which have already been set.
.Sh SEE ALSO
.Xr iscsi-initiator 8 ,
.Xr iscsi-target 8
.Sh HISTORY
The
.Nm
library first appeared in
.Nx 4.0 .
This programmatic interface to the
iSCSI subsystem
first appeared in
.Nx 6.0 .
.Sh AUTHORS
.An Alistair Crooks Aq Mt agc@NetBSD.org .