.TH SDLOOP 3
.SH NAME
sdloop \- loopback storage device interface
.SH SYNOPSIS
.nf
.B bind -a #S /dev
.BI "echo config switch on spec " l " type loop/\fIpath\fP[!\fIsectsize\fP] >/dev/sdctl"

.BI /dev/sd l 0/ctl
.BI /dev/sd l 0/raw
.BI /dev/sd l 0/data
\&...
.fi
.SH DESCRIPTION
.I Sdloop
allows a file to be used as a sd device.
To configure
.B /tmp/data
as
.BR sdl0 :
with a 1024-byte sector size
.IP
.EX
echo config switch on spec l type loop//tmp/data!1024 >/dev/sdctl
.EE
.PP
To turn this device off,
.IP
.EX
echo config switch off spec l >/dev/sdctl
.EE
.PP
The configuration variable
.B loopdev
may be specified in
.IR plan9.ini (8)
to configure a loopback 
.I sd
device at boot.  For example
.IP
.EX
loopdev=l!/tmp/data!1024
.EE
.SH SOURCE
.B /sys/src/9/port/sdloop.c
.SH SEE ALSO
.IR sd (3),
.IR sdaoe (3),
.IR partfs (8)
.SH BUGS
Maybe.