My script use many file descriptors. Too many. Maximum.
The problem is: how I can test how much file descriptors still available for my process?
My current solution is too slowly for me: 
sub FD_used {
    local *FD; opendir FD, "/proc/self/fd";
    return @{[readdir FD]} - 2;
};

[download]
I need something faster. Any ideas?

Background: this script is a very quick "spider", which use non-blocking sockets to reach speed > 200 urls per second. So i open many simultaneous connections. Some of them is UDP sockets to DNS server, other is TCP sockets to HTTP servers. And more connections mean more urls per second. So, now I open ~ 200 sockets in a second. And I need to test how many sockets opened before trying to open new socket. But 200 calls of my FD_used() take too many time (0.05 sec on Celeron 333) and slow other code! Errr!!

In reply to resource control: FD by powerman

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