Re: Event loop and http::geturl

On 6/24/2025 5:19 PM, et99 wrote:

On 6/24/2025 1:01 AM, Jonathan Kelly wrote:

OK. Is there a way to ACTUALLY get geturl to block, or equivalent? I need the geturl to finish before anything else happens.

 I would think you can use this option on the geturl call:
 -command callback
  

I see you already know about -command, so perhaps what you really want is an example of how to use it.
proc httpCallback {token} { ;# the -command callback - called when transaction completes
     upvar 0 $token state    ;# use this to get the results
     set ::urldone 1         ;# block on the setting of this variable
     return
}
unset -nocomplain ::urldone :# rules out a race condition
http::geturl <your url> -command httpCallback
if {![info exists ::urldone]} {vwait ::urldone} ;# no need to block if the variable exists
The above code is being cautious. There may not be any possibility of a race condition, but this way we rule it out, even if they change the code in the future. It never hurts to unset a variable first that you're going to set later anyway.