in reply to how to stop command

my $file;
my @file_list;
foreach $file(@file_list){
print "$file\n";
}

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This will achieve nothing, ever. @file_list is empty so the loop will not be entered. Is this the source of your confusion? If so, declare @file_list before the eval instead and then don't re-declare it inside.

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Re^2: how to stop command
by dideod.yang (Sexton) on Jul 22, 2018 at 10:29 UTC
    Hi :) you mean below script? 
     my $timeout = 5;
 eval {
        local $SIG{ALRM} = sub { die "alarm\n" }; 
        alarm $timeout;
        my @file_list = `ls user/test/`;       
        my $file;
        my @file_list;
        foreach $file(@file_list){
        print "$file\n";
         }
        alarm 0;
    };
    if ($@) {
        die unless $@ eq "alarm\n";   # propagate unexpected errors
        # timed out
    }
    else {
        # didn't
    }

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[reply]
[d/l]

      Not quite. I mean more like this:

      my $timeout = 5;
my @file_list;

eval {
       local $SIG{ALRM} = sub { die "alarm\n" };
       alarm $timeout;
       @file_list = `ls user/test/`;
       alarm 0;
};
if ($@) {
    die $@ unless $@ eq "alarm\n";   # propagate unexpected errors
    # timed out
    print "Have incomplete file list\n";
} else {
    print "Have complete file list\n";
}

foreach my $file (@file_list) {
    print "$file\n";
}

      [download]
[reply]
[d/l]

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