TCL：超時一個可能掛起的proc

Question

我創建了一個proc，它可能只是根據輸入而懸掛在那裏。現在我想爲它設置一個超時值，並強制它返回並在時間到期後繼續其他工作。

vwait的方式似乎不適用於我的情況在這裏。如果我把我的vwait PROC後，如：

after sometime set status timeout 
proc_may_hang 
vwait status 

如果PROC掛起時，vwait永遠不會被執行，事件循環從來沒有得到啓動和系統不知道或者監視變量狀態。

而且我也無法使用多線程來啓動監視進程。 TCL解釋器來自EDA軟件，Thread包不可用。

那麼有沒有辦法強制proc返回？非常感謝！

Answer 1

線程可以幫助，但需要一些連線。這是殺死長時間運行的線程的線程示例。

package require Thread 

# Create a thread with needed procs for calculation.=. 

proc spawn {} { 
    set t_id [thread::create { 

     # Source your program here. 
     # Make sure to have thread::release when calculation is final. 
     # source myfile.tcl 

     # this is an example proc 
     proc do_calculation {params} { 
      # add this to your program 
      # get your params for calculation from item 
      foreach {parent_id callback index item} $params {} 

      set i 10000 

      while {$i > 0} { 
       incr i $item 
       if {$i > 99999} { 
        set i 10000 
       } 
      } 

      # Run something when calculation is done here... 
      puts "All done! i = $i" 

      # Or in the parent thread in item_complete 
      thread::send -async $parent_id [list $callback $index $item] 
      thread::release 
     } 

     # Don't change beleow. The thread::wait keeps the thread running 
     # so can send it a command. 
     thread::wait 
    }] 
} 

proc check_thread {t_id seconds callback {started 0}} { 

    # If the thread doesn't exist then it probably finished and called thread::release. 
    if {[thread::exists $t_id] == 0} { 
     $callback 
     return 
    } 

    # Check the time remaining for the thread to complete. 
    set now [clock seconds] 

    if {$started == 0} { 
     set started $now 
    } 

    set seconds_remaining [expr {$seconds - ($now - $started)}] 

    puts "$seconds_remaining seconds remaining." 

    # Stop the thread if it took too long. 
    if {$seconds_remaining < 1} { 
     puts "Times up... stopping thread `$t_id`." 
     thread::release $t_id 
     $callback 
     return 
    } 

    # Check the thread again in 1 second. 
    after 1000 [list check_thread $t_id $seconds $callback $started] 
} 

# some fake data. Package your data into a list of items to process. 
set items [list 1 -1 9 -9 20 -20] 
set items_i 0 

proc next_item {} { 
    global items 
    global items_i 

    if {$items_i < [llength $items]} { 
     set item [lindex $items $items_i] 
     incr items_i 
     set t_id [spawn] 
      # Tell the thread to run the calculation. 
      thread::send -async $t_id [list do_calculation [list [thread::id] item_complete $items_i $item]] 
     check_thread $t_id 10 next_item 
    } else { 
     puts "Items completed. exiting." 
     exit 
    } 
} 

proc item_complete {index item} { 
    puts "Item #${index} completed successfully. Item = ${item}." 
} 

next_item 

vwait forever