Hello
The spec does not allow for carriage returns or line feeds making it
a long line. Is there a way to read "x" number of bytes?
Andrew
At 11:10 AM 5/25/2008, Rob Dixon wrote:
Hi Andrew
(If you are asking a new question of this group please make a fresh
post with an
appropriate subject line rather than replying to the end of an old
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of us have email clients that correctly display the flow of threads, and using
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Thanks.)
> I have been reading files with the following command:
>
> @source_lines = (<SOURCE_FILE>);
>
> This has worked until I started reading some very large files.
This reads the entire file into the array, and should only be used for files
that you can guarantee to be very small. As you have found, filling up your
computer's memory isn't a good idea!
> Is there a better way to read files? The files I am trying to read now are
> about 300 megabytes in size.
In most cases you will need access to only one record at a time.
Writing a loop
like this
while (<SOURCE_FILE>) {
chomp;
process_record($_);
}
will minimize your memory usage and almost certainly run much faster.
> The bad news is that the spec has no carriage returns or line
feeds. We have
> no control over the spec. I need to replace a few characters in the file.
The end of each file record must be defined somehow. Either there is a
terminating characters sequence or the records are fixed-size, or
possibly they
are variable-sized with the actual size specified earlier in the file. Take
another look at your file spec.
HTH,
Rob
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