in reply to Re: running same bit of code twice
in thread running same bit of code twice

Hi pfaut,

I'm interested in the phrasing of the open command: 

open FH,"<",$datafile or die "Could not read virtual file";

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I habitually use: 
open FH, "$datafile" or die "Can't open $datafile: $!";

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although I'm aware of the  < being an 'open for read only' tag I would use it as follows: 
open FH, "< $datafile" or die "Can't open $datafile: $!";

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I wondered if you would talk me through your use of it and why you might consider it necessary to use   < at all.

Thanks for your help

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Re: Re: Re: running same bit of code twice
by belg4mit (Prior) on May 04, 2003 at 18:43 UTC
    3-arg open is considered more secure than 2-arg open, as perl won't be looking to change it's behavior based upon any special characters (such as < > |) (update: in the filename). Since 3-arg open has no default (you can't leave the second arg undefined), you must explicitly indicate "open for read-only". Finally, some people simply like to be explicit. Why would you write 
    foreach my $apple (qw(McIntosh Empire Gala)){ $apple }

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    When this would do just fine 
    foreach (qw(McIntosh Empire Gala)){ $_ }

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    --
    I'm not belgian but I play one on TV.

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