The '''main script''' is the primary script that is executed by the interpreter
, e.g. [tclsh] or [wish] .



** Description **

One common technique is to have a script run a self test if it detects that it
is the main script .  The following more complete detection method is required
for correct behaviour when [pkg_mkIndex] is being used:

======
if {[info exists argv0] && [file tail [info script]] eq [file tail $argv0]} {
    #do stuff
}
======

Another variation :

======
if {![info exists argv0] || [
  file tail [info script]] ne [file tail $argv0]} return

# test/standalone code follows
======

The more simple and naive approach to detection method only compares `[info
script]` with `$[argv0]` :

======
if {[info exists argv0] && $argv0 eq [info script]} {
    #do stuff
}
======

or , as formulated in a [comp.lang.tcl] posting by [DKF]:

======
if {[string equal $::argv0 [info script]] || [
    array exists ::embed_args]} {
    main
} 
======



** authors **

   [dfk] :   

   cjl :   

   [PYK] :   

   [RS] :