Re: Opening two files at once

[drieux]

On Dec 22, 2003, at 4:32 PM, [EMAIL PROTECTED] wrote:

I have two text files I would like to open and read at the same time.
Whats the best way to do this?
the only problem with your current form, barring
the faux paux of
        while( ($line1 = <TESTFILE>) && ($line2 = <LOGFILE>))
        {
	}

is what to do with the case of one file being longer than
the other file.
So you might try the idea of

        my ($line1, $line2 , $flag );
        while ( 1 ) {
                $line1 = <TESTFILE>; # read them each
                $line2 = <LOGFILE>;
                last unless ( $line1 || $line2 ); # if both empty exit loop
                #
                # otherwise test for which one just finished
                #
                unless( $line1 )
                {
                        $flag = 1;
                        last;
                }
                unless( $line2 )
                {
                        $flag = 2;
                        last
                }
                #
                # now do the voodo on the two lines
                #
                chomp($line2);
                chomp($line1);
                print "$line2 : $line1\n";
        }
        # if one needs to know which ended first one
        # can deal with that here...
        if ( $flag )
        {
                print "more lines to read\n";
                print "\tfrom TestFile \n" if ( $flag == 1 );
                print "\tfrom logfile \n" if ( $flag == 2 );
        } else {
                print "both ended together\n";
        }
        # now one would be safe to close the files
HTH.

ciao
drieux
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