Taskkill inside TCL script (using foreach) is not working

Question

I need to browse a URL using Internet Explorer, and close using taskkill through TCL script. I am using following TCL script for this.

My TCL Script:

set data [open input_url.txt r]
set test [read $data]
foreach url $test {
    exec "C:/Program Files/Internet Explorer/IEXPLORE.EXE" $url
    after 2000
    exec "C:/WINDOWS/System32/taskkill.exe" /IM IEXPLORE.EXE /F
}

input_url.txt content:

clickshare upload.com upload.to 10upload.com 123upload.pl 139pan.com 163pan.com

But When I run this script, Browser with first URL is opened. But nothing is happening after this. After 2-3 minutes, if I close the browser manually, I am seeing the following error:

C:\Users\kumar\Desktop\test>tclsh stack_question.tcl
child process exited abnormally
while executing
"exec "C:/Program Files/Internet Explorer/IEXPLORE.EXE" $url"
    ("foreach" body line 2)
    invoked from within
"foreach url $test {
    exec "C:/Program Files/Internet Explorer/IEXPLORE.EXE" $url
        after 2000
   exec "C:/WINDOWS/System32/taskkill.exe" /IM IEXPLO..."
    (file "stack_question.tcl" line 3)
   C:\Users\kumar\Desktop\test>

I am able to kill the browser session manually using taskkill.exe as shown below:

C:\Users\kumar\Desktop\test>tclsh
% exec "C:/WINDOWS/System32/taskkill.exe" /IM IEXPLORE.EXE /F
SUCCESS: The process "iexplore.exe" with PID 3948 has been terminated.
SUCCESS: The process "iexplore.exe" with PID 3744 has been terminated.
%

Could any one please help me to fix this issue?

Thanks in advance.

Answer 1

It seems like exec is waiting for iexplore.exe to finish before it continues execution. In order to allow immediate return use start command:

exec cmd.exe /c start iexplore.exe $url

This will return immediately.