Close a tcl server after file copy is complete - network-programming

Question

I am running a tcl server in VM and a client in windows machine to copy a file from client to vm. The problem is I want the server to close automatically after the task is done. Currently it is not doing it , because "vwait" is set to "forever" .I don't have much knowledge about tcl network programming ,so I can't figure out how to implement it.
My server code
##server side
set destination_directory /home/media
set service_port 9900
proc receive_file {channel_name client_address client_port} {
fconfigure $channel_name -translation binary
gets $channel_name line
foreach {name size} $line {}
set fully_qualified_filename [file join $::destination_directory $name]
set fp [open $fully_qualified_filename w]
fconfigure $fp -translation binary
fcopy $channel_name $fp -size $size
close $channel_name
close $fp
}
socket -server receive_file $service_port
vwait forever
and my client code:
##client side
set service_port 9900
set service_host 192.168.164.161
proc send_one_file name {
set size [file size $name]
set fp [open $name]
fconfigure $fp -translation binary
set channel [socket $::service_host $::service_port]
fconfigure $channel -translation binary
puts $channel [list $name $size]
fcopy $fp $channel -size $size
close $fp
close $channel
}
send_one_file "sample.pdf"
Please guide.

Answer 1

Add one more line to the receive_file proc after you close the handles:
set ::forever true ;# or any other value at all

Answer 2

If you want the Tcl script to terminate after the transfer is done, you can just exit after the close.
set destination_directory /home/media
set service_port 9900
proc receive_file {channel_name client_address client_port} {
fconfigure $channel_name -translation binary
gets $channel_name line
foreach {name size} $line {}
set fully_qualified_filename [file join $::destination_directory $name]
set fp [open $fully_qualified_filename w]
fconfigure $fp -translation binary
fcopy $channel_name $fp -size $size
close $channel_name
close $fp
exit ; #### All done with this process
}
socket -server receive_file $service_port
vwait forever
However, it is probably better to use the asynchronous form of fcopy (I've added a bunch of other Tcl 8.5-isms in here too):
set destination_directory /home/media
set service_port 9900
proc receive_file {channel client_address client_port} {
global destination_directory
lassign [gets $channel] name size
fconfigure $channel -translation binary
if {[catch {
set fp [open [file join $destination_directory $name] "wb"]
fcopy $channel $fp -size $size -command [list done_transfer $channel $fp]
}]} exit
}
proc done_transfer {from_channel to_channel bytes {errorMessage ""}} {
close $from_channel
close $to_channel
exit
}
socket -server receive_file $service_port
vwait forever
A production version of this would probably have code in there to guard against bad filenames, do logging, and possibly to allow multiple connections to be made and for those connections to all finish before the server script finishes. All that makes the code quite a bit longer…