Japhy et al,
This worked perfectly for what I want to do.
Thanks to all of you, I am learning at a greater rate than by working alone.
Many thanks.
At 04:32 PM 6/30/04 -0400, Jeff 'japhy' Pinyan wrote:
>On Jun 30, David Arnold said:
>
>>As I begin reading in lines from the file, I just print them until I hit a
>>line that has an opening "\ex" in it. At that point I want to accumulate
>>lines in one long string until I hit either "\begin{instructions}" or
>>another "\ex".
>>
>>$line.=<IN> #unless the current line coming in from IN is the start
>> #of a new \ex or a \begin{instructions}
>>
>>The difficulty is now I've read one line too many. I'd like to "put this
>>last line back" for the next round of reading while I process the
>>accumulated exercise lines.
>
>I would suggest the following approach:
>
> # some bigger loop
> while (...) {
> my $line = "";
>
> while (<IN>) {
> if (/\\ex|\\begin{instructions}/) {
> seek IN, -length, 1;
> last;
> }
> $line .= $_;
> }
> }
>
>This uses the seek() function to go to a position in the file. The last
>argument, 1, means we're moving relative to where we are now. The middle
>argument, -length, is the number of bytes to move. So if the line is 20
>characters long, we're going 20 characters back from where we are now,
>essentially to the start of the line.
>
>--
>Jeff "japhy" Pinyan [EMAIL PROTECTED] http://www.pobox.com/~japhy/
>RPI Acacia brother #734 http://www.perlmonks.org/ http://www.cpan.org/
>CPAN ID: PINYAN [Need a programmer? If you like my work, let me know.]
><stu> what does y/// stand for? <tenderpuss> why, yansliterate of course.
>
>
>
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