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Full Discussion: fork() in for loop
Top Forums Programming fork() in for loop Post 25980 by Perderabo on Thursday 8th of August 2002 01:09:26 PM
Old 08-08-2002
fork() makes a copy of a process. If you do that in a "for" loop, you have a problem. The first time through the loop you invoke fork() and now you have two processes. Unless you have code to prevent it, both processes with continue to run that loop. On the second iteration you get 4 processes, then 8, then 16, then 32.... Anr 32 processes all forking themselves will put a nasty load on the system.
 

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continue(3tcl)						       Tcl Built-In Commands						    continue(3tcl)

__________________________________________________________________________________________________________________________________________________

NAME
continue - Skip to the next iteration of a loop SYNOPSIS
continue _________________________________________________________________ DESCRIPTION
This command is typically invoked inside the body of a looping command such as for or foreach or while. It returns a TCL_CONTINUE code, which causes a continue exception to occur. The exception causes the current script to be aborted out to the innermost containing loop command, which then continues with the next iteration of the loop. Catch exceptions are also handled in a few other situations, such as the catch command and the outermost scripts of procedure bodies. EXAMPLE
Print a line for each of the integers from 0 to 10 except 5: for {set x 0} {$x<10} {incr x} { if {$x == 5} { continue } puts "x is $x" } SEE ALSO
break(3tcl), for(3tcl), foreach(3tcl), return(3tcl), while(3tcl) KEYWORDS
continue, iteration, loop Tcl continue(3tcl)
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