Inifinite Loop on fork Post: 302447807

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Top Forums Shell Programming and Scripting Inifinite Loop on fork Post 302447807 by popeye on Tuesday 24th of August 2010 11:03:18 AM

08-24-2010

Registered User

Inifinite Loop on fork

I am trying to ping through a list of devices in parallel.
When the code below is executed, I enter a infinite loop.
I want to used the number of lines in the file as my boundry.

I am a perl rookie and just cant see whats wrong.
would appreciate help ...

Code:

use Net::Ping;
#
$filename = <@ARGV>;
open(CONT, $filename) or die "can't open $file: $!";
$bndry++ while <CONT>;
print $bndry;
close(CONT);
#
open(FILE, $filename) or die "can't open $file: $!";
while(<FILE>) {
 $ip = $_;
  chomp $ip;
  if (fork() == 0) {
$pingo = Net::Ping->new();
 if ($pingo->ping("$ip")) {print "Pinging $ip:\t Status:\tOk\n";}
 else {
     print ("Pinging $ip:\t Status:\tNot Ok\n");
 }
 $pingo->close();
    exit;
  }
  $children++;
 # if ($children >= $bndry) {
  if ($children >= 51) {
    wait();
    $children--;
  }
}
while ($children > 0) {
  wait();
  $children--;
}
exit 0;

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LEARN ABOUT REDHAT

xquerytree

XQueryTree(3X11)						  XLIB FUNCTIONS						  XQueryTree(3X11)

NAME

       XQueryTree - query window tree information

SYNTAX

       Status XQueryTree(display, w, root_return, parent_return, children_return, nchildren_return)
	     Display *display;
	     Window w;
	     Window *root_return;
	     Window *parent_return;
	     Window **children_return;
	     unsigned int *nchildren_return;

ARGUMENTS

       children_return
		 Returns the list of children.

       display	 Specifies the connection to the X server.

       nchildren_return
		 Returns the number of children.

       parent_return
		 Returns the parent window.

       root_return
		 Returns the root window.  you want to obtain

       w	 Specifies the window whose list of children, root, parent, and number of children.

DESCRIPTION

       The XQueryTree function returns the root ID, the parent window ID, a pointer to the list of children windows (NULL when there are no chil-
       dren), and the number of children in the list for the specified window.	The children are listed in current stacking order, from bottom-
       most (first) to top-most (last).  XQueryTree returns zero if it fails and nonzero if it succeeds.  To free a non-NULL children list when it
       is no longer needed, use XFree.

BUGS

       This really should return a screen *, not a root window ID.

SEE ALSO

       XFree(3X11), XGetWindowAttributes(3X11), XQueryPointer(3X11)
       Xlib - C Language X Interface

X Version 11							    Release 6.6 						  XQueryTree(3X11)

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