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From: jeffg on 14 Apr 2008 16:31
I'm trying to use CSV_XS to parse log files.
Each field is separated by a comma and surround by double quotes.

Within each field, there may be embdedded double and single quotes.
These embedded quotes are escaped by a backslash.

I'm having trouble getting it to work. I have two questions:

1) The entire script fails at the first line it can't parse. How can
I make it ignore the current line and continue?
I'm using getline() to read the file, like this:

open my $io, "<", $logname or warn("Cannot open file ${logname} for
reading. $!");
while (my $line = $csv->getline($io)) {

}

2) How should I instantiate my $csv object to get it to recognize my
escape character?

I tried this:

my $csv = Text::CSV_XS->new( {
escape_char => '\\',
sep_char => ',',
binary => 1,
} );

From: Ben Morrow on 14 Apr 2008 16:49

Quoth jeffg(a)programmer.net:
> I'm trying to use CSV_XS to parse log files.
> Each field is separated by a comma and surround by double quotes.
>
> Within each field, there may be embdedded double and single quotes.
> These embedded quotes are escaped by a backslash.
>
> I'm having trouble getting it to work. I have two questions:
>
> 1) The entire script fails at the first line it can't parse. How can
> I make it ignore the current line and continue?
> I'm using getline() to read the file, like this:
>
> open my $io, "<", $logname or warn("Cannot open file ${logname} for
> reading. $!");

You want to die at this point, not warn. There's no point continuing if
the open failed: $io is undef, and the rest of the program will just
give unhelpful errors.

> while (my $line = $csv->getline($io)) {
>
> }

->getline returns false on EOF or on parse error. You can tell the
difference with ->eof; something like

CSV:
while (my $line = $csv->getline($io)) {
...
}

unless ($csv->eof) {
warn "bad line in CSV file\n";
redo CSV;
}

Alternatively you could read the lines in yourself and call ->parse on
them; that way you can show the user what the bad line looked like. Be
careful to make sure you get complete records, if you do this.

> 2) How should I instantiate my $csv object to get it to recognize my
> escape character?
>
> I tried this:
>
> my $csv = Text::CSV_XS->new( {
> escape_char => '\\',
> sep_char => ',',
> binary => 1,
> } );

It looks to me as though you need the allow_loose_escapes option, to
allow you to escape ' when it doesn't really need it.

Ben

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