11-06-2012
Quote:
Originally Posted by
royalibrahim
I Just want to understand whether in Perl, is it possible to iterate over a file object using a for loop as I did in my code? Perl complains no error even if you use it.
Of course, yes. You did it, right?
Why would perl complain when what you were doing was syntactically correct but logically wrong?
Never use a for (or foreach) loop to read a file. In this case, all lines from the file (depending on the input record separator) will be read in at once and stored in memory to form a list. Your loop will then iterate over the elements of this list. So, you might hit your system's memory limits.
A while loop is much much better as it reads one record at a time.
This User Gave Thanks to elixir_sinari For This Post:
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NAME
mewl - Message scanner for Mew 4 or later
SYNOPSIS
mewl [options] [folder [range]]
DESCRIPTION
The mewl utility extracts necessary fields from messages stored in folders. This command is necessary for Mew to implement the asynchro-
nous feature.
The options are as follows:
-a Print all necessary fields when picking.
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-c bodylen
Set the max body length to be extracted to bodylen.
-d field
Set the field to be extracted to field.
-e command
Specify an external command to fetch mailbox.
-m options
Specify options for command.
-f fields
Specify fields to display.
-h Display this help message.
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-l length
Set the max field length to be extracted to length. The default value is 3. 0 means no limit.
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-p pattern
Specify the pick pattern.
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-v Display the version.
-x suffix
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Definitions of the symbols above are as follows:
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BUGS
If a field is long, only the beginning three lines are extracted by default.
March 5, 2003 MEWL(1)