Contributed by Anonymous Monk
on Apr 18, 2001 at 09:57 UTC
Q&A
> files
Answer: how can we read each line from a file onto an array? contributed by OeufMayo my @lines = <FILE>;
But beware, as the perlfaq 5 says:
Whenever
you see someone do this:
@lines = <INPUT>;
You should think long and hard about why you need everything loaded
at once. It's just not a scalable solution. You might also find it
more fun to use the the standard DB_File module's $DB_RECNO bindings,
which allow you to tie an array to a file so that accessing an element
the array actually accesses the corresponding line in the file.
| Answer: how can we read each line from a file onto an array? contributed by tye my @lines= do { local(*ARGV); @ARGV="filename.txt"; <> };
is one way to avoid having to open the file explicitly, check for errors, and report them. | Answer: how can we read each line from a file onto an array? contributed by davorg open FILE, '/path/to/file'
or die "Can't open file: $!\n";
my @array = <FILE>;
All very simple :)
| Answer: how can we read each line from a file onto an array? contributed by abhishek_akj my @lines = <FILE>
above loads the whole file at once in memory.
Instead, you can do something like
while(my $line=<FILE>){
do_something;
}
This code will still traverse the whole file, so wont be faster but it will load only one line at a time in the memory - helpful if you want to parse 4GB file and have only 2 GB RAM ;) | Answer: how can we read each line from a file onto an array? contributed by Clachair use IO::File;
open ($fhi, $fi) || die "$!, Couldn't open file $fi";
@lines = $fhi->getlines;
foreach $lines(@lines) {
# Select only those lines with a HTML cell bg color spec;
if ($lines =~ /^\s*<td bgcolor/) {push @List, $lines; }
}
closedir ($fhi, $fi);
Clachair.
Never lick a gift horse in the mouth. |
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