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.HS dp_atclose cmds


.SH NAME
.BS
dp_atclose \- arrange for commands to be evaluated when a file or socket
is closed
.BE
.TP
\fBdp_atclose \fIsockId\fR option ?\fIcmd\fR?

The dp_atclose command manages the \fIdp_atclose list\fP, a list of
callback routines that are evaluated just before \fIsockId\fP is actually
closed.  This is useful for networking applications, where filehandlers
associated with a socket must be deleted when a socket is closed.

The argument \fIoption\fP specifies the operation to be performed
on the dp_atclose list.  The valid options are:

.RS
.TP
\fBdp_atclose \fIsockId\fR list

Returns the current dp_atclose list associated with \fIsockId\fR.

.TP
\fBdp_atclose \fIsockId\fR set \fInewList\fP

Sets the dp_atclose list associated with \fIsockId\fR to \fInewList\fP.

.TP
\fBdp_atclose \fIsockId\fR append \fIcallback\fP

Append \fIcallback\fP to the end of the dp_atclose list associated with
\fIsockId\fR.

.TP
\fBdp_atclose \fIsockId\fR appendUnique \fIcallback\fP

Appends \fIcallback\fP to the end of the dp_atclose list associated with
\fIsockId\fR if it's not already a member of the list.

.TP
\fBdp_atclose \fIsockId\fR prepend \fIcallback\fP

Inserts \fIcallback\fP at the front of the dp_atclose list associated
with \fIsockId\fR.

.TP
\fBdp_atclose \fIsockId\fR insert \fIbeforeCallback\fP \fIcallback\fP

Inserts \fIcallback\fP before \fIbeforeCallback\fP in the dp_atclose
list associated with \fIsockId\fR.  If \fIbeforeCallback\fP is not in
the dp_atclose list associated with \fIsockId\fR, no action is taken.

.TP
\fBdp_atclose \fIsockId\fR delete \fIcallback\fP

Delete \fIcallback\fP from the dp_atclose list associated with
\fIsockId\fR. If \fIcallback\fP is not in the dp_atclose list associated
with \fIsockId\fR, no action is taken.

.TP
\fBdp_atclose \fIsockId\fR clear

Clears the dp_atclose list associated with \fIsockId\fR.

.SH AUTHOR
Brian Smith (bsmith@cs.berkeley.edu)
.br
Steve Yen (syen@cs.berkeley.edu)
