'\" te
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.TH SCSI_POLL 9F "Jan 16, 2006"
.SH NAME
scsi_poll \- run a polled SCSI command on behalf of a target driver
.SH SYNOPSIS
.nf
#include <sys/scsi/scsi.h>



\fBint\fR \fBscsi_poll\fR(\fBstruct scsi_pkt *\fR\fIpkt\fR);
.fi

.SH INTERFACE LEVEL
illumos DDI specific (illumos DDI).
.SH PARAMETERS
.ne 2
.na
\fB\fIpkt\fR\fR
.ad
.RS 7n
Pointer to the \fBscsi_pkt\fR(9S) structure.
.RE

.SH DESCRIPTION
The \fBscsi_poll()\fR function requests the host adapter driver to run a polled
command. Unlike \fBscsi_transport\fR(9F) which runs commands asynchronously,
\fBscsi_poll()\fR runs commands to completion before returning. If the
\fBpkt_time\fR member of \fIpkt\fR is \fB0\fR, the value of  \fBpkt_time\fR is
defaulted to \fBSCSI_POLL_TIMEOUT\fR to prevent an indefinite hang of the
system.
.SH RETURN VALUES
The \fBscsi_poll()\fR function returns:
.sp
.ne 2
.na
\fB\fB0\fR\fR
.ad
.RS 6n
command completed successfully.
.RE

.sp
.ne 2
.na
\fB\fB-1\fR\fR
.ad
.RS 6n
command failed.
.RE

.SH CONTEXT
The \fBscsi_poll()\fR function can be called from user, interrupt, or kernel
context. This function should not be called when the caller is executing
\fBtimeout\fR(9F) in the context of a thread.
.SH SEE ALSO
.BR makecom (9F),
.BR scsi_transport (9F),
.BR scsi_pkt (9S)
.sp
.LP
\fIWriting Device Drivers\fR
.SH WARNINGS
Since \fBscsi_poll()\fR runs commands to completion before returning, it may
require more time than is desirable when called from interrupt context.
Therefore, calling \fBscsi_poll\fR from interrupt context is not recommended.