Here is a version using Text::ParseWords and a modified spawn subroutine, which uses exec in scalar context. This allows parameterized command execution.
#!/usr/bin/perl
use Getopt::Std;
use Text::ParseWords;
my %opt = (n => 1);
getopts('r:n:v', \%opt) or usage();
my $cmd = shift;
@ARGV = shuffle(@ARGV) if $opt{r};
my %pid;
while (@ARGV) {
if (keys(%pid) < $opt{n}) {
$pid{spawn($cmd, map { shellwords($_) } shift @ARGV)} = 1;
} else {
delete $pid{wait()};
}
}
1 while wait() >= 0;
sub spawn {
my $pid = fork;
die "fork: $!" unless defined $pid;
return $pid if $pid;
warn "@_\n" if $opt{v};
exec qq(@_);
die "exec: $!";
}
sub usage {
print STDERR "Usage: $0 [-n N] [-r] [-v] command arg1 arg2...
Run command arg1, command arg2, etc., concurrently.
Run no more than N processes simultaneously (default 1)
-r: run commands in random order instead of specified order (unimp
+l.)
-v: verbose mode
";
exit 1;
}
The following snippet will ping google.com and amazon.com once in the first chunk and yahoo.com in the second.
runN -v -n 2 'ping -n 1' google.com amazon.com yahoo.com
ping -n 1 google.com
ping -n 1 amazon.com
Ping google.com [72.14.207.99] mit 32 Bytes Daten:
Antwort von 72.14.207.99: Bytes=32 Zeit=116ms TTL=242
Ping-Statistik für 72.14.207.99:
Pakete: Gesendet = 1, Empfangen = 1, Verloren = 0 (0% Verlust),
Ca. Zeitangaben in Millisek.:
Minimum = 116ms, Maximum = 116ms, Mittelwert = 116ms
Ping amazon.com [72.21.210.11] mit 32 Bytes Daten:
ping -n 1 yahoo.com
Ping yahoo.com [66.94.234.13] mit 32 Bytes Daten:
Antwort von 66.94.234.13: Bytes=32 Zeit=185ms TTL=54
Ping-Statistik für 66.94.234.13:
Pakete: Gesendet = 1, Empfangen = 1, Verloren = 0 (0% Verlust),
Ca. Zeitangaben in Millisek.:
Minimum = 185ms, Maximum = 185ms, Mittelwert = 185ms
Zeitüberschreitung der Anforderung.
Ping-Statistik für 72.21.210.11:
Pakete: Gesendet = 1, Empfangen = 0, Verloren = 1 (100% Verlust)
print+qq(\L@{[ref\&@]}@{['@'x7^'!#2/"!4']});