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.TH "USB_UNLINK_URB" "9" "06 August 2003" "" ""

.SH NAME
usb_unlink_urb \- abort/cancel a transfer request for an endpoint
.SH SYNOPSIS
.sp
\fB
.sp
int usb_unlink_urb  (struct urb * \fIurb\fB);
\fR
.SH "ARGUMENTS"
.TP
\fB\fIurb\fB\fR
pointer to urb describing a previously submitted request
.SH "DESCRIPTION"
.PP
This routine cancels an in-progress request.  The requests's
completion handler will be called with a status code indicating
that the request has been canceled, and that control of the URB
has been returned to that device driver.
.PP
When the URB_ASYNC_UNLINK transfer flag for the URB is clear, this
request is synchronous.  Success is indicated by returning zero,
at which time the urb will have been unlinked,
and the completion function will see status -ENOENT.  Failure is
indicated by any other return value.  This mode may not be used
when unlinking an urb from an interrupt context, such as a bottom
half or a completion handler,
.PP
When the URB_ASYNC_UNLINK transfer flag for the URB is set, this
request is asynchronous.  Success is indicated by returning -EINPROGRESS,
at which time the urb will normally not have been unlinked,
and the completion function will see status -ECONNRESET.  Failure is
indicated by any other return value.
.SH "ABOUT THIS DOCUMENT"
.PP
This documentation was generated with kernel version 2.6.0.