Contributed by C_Mangano
on Apr 03, 2000 at 21:14 UTC
Q&A
> files
Description: I know how to use the while (<>){} method of reading from a file, but my question is this. What if ARGV is given a folder name. Then, a subroutine parses all the folders below this folder, until it gets to a file. Now I want to be able to read a line from that file. Any help would be greatly appreciated. Thanks. Answer: How do I read from a file, that was read from a directory? contributed by chromatic Use the -d test to see if the argument is a directory (perldoc -f -X). Use glob to get a list of all files in that directory. Repeat until you reach a file. (-d $file will be false). Then, open that file and read a line from it. Code might look something like this:
my $possible_file = shift;
my $found_file = find_file($possible_file);
{
local *INPUT;
open(INPUT, $found_file) or die "Can't open $found_file: $!";
my $line = <INPUT>;
# do something with $line
close INPUT or die "Can't close $found_file. Bogosity: $!";
}
sub find_file {
my $file = shift;
while (-d $file) {
# the next line may differ on Win/Mac/Un*x
my @files = glob("$possible_file/*.*");
foreach (@files) {
find_file($_);
}
# we're not dealing with a file anymore, so return
}
return $file;
}
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