Tcl API Reference -- ns_sockcallback

### ns_sockcallback

#### Overview

Register a socket callback script

#### Syntax

ns_sockcallback sockid script when

#### Description

ns_sockcallback registers a socket callback script. The script should accept the arguments sockid and when. The script will be called according to the value of the when argument as follows:

Value of when: | Condition under which the script will be called:
--- | ---
r | the socket is readable
w | the socket is writeable
e | the socket has an exceptional condition
x | the server is shutting down

#### Example

        set sock [ns_socklisten * 9000]
        ns_sockcallback $sock newconn r
        # Keep $sock from closing after connection ends
        detach $sock
        # When a connection arrives, newconn will be called as:
        # newconn $sock r
        proc newconn {sock when} {
        set fds [ns_sockaccept $sock]
        set rfd [lindex $fds 0]
        set wfd [lindex $fds 1]
        puts $wfd "Hello!"
        close $rfd
        close $wfd
        }

#### See Also

Ns_SockCallback

Top of Page
Copyright © 1998-99 America Online, Inc.