perldoc -f seek /Stefan Lidman
Paul Kraus wrote: > > How do I look up info for a fuction like seek. I tried perldoc seek and > perldoc Seek to no avail. > > Thanks. > > > -----Original Message----- > > From: Bob Showalter [mailto:[EMAIL PROTECTED]] > > Sent: Thursday, December 05, 2002 2:14 PM > > To: 'Paul Kraus'; Perl > > Subject: RE: Snagging the last page of a report > > > > > > > -----Original Message----- > > > From: Paul Kraus [mailto:[EMAIL PROTECTED]] > > > Sent: Thursday, December 05, 2002 2:00 PM > > > To: Perl > > > Subject: Snagging the last page of a report > > > > > > > > > Every month I have several reports I print to disk. They are > > > hundreds of > > > pages long. I only need the last page of each. As it is now I > > > open it in > > > a text editor scroll down and copy the last page to a new > > > text document. > > > This is irritating and I want to play with the Perl I have been > > > learning. > > > > > > How can I snag the last page of something. > > > > > > I could do a search to find end of file (I think you can do > > that with > > > reg expr). > > > > No, regexes are for searching strings. The seek() function > > can be used to position the pointer at the end of the file. > > > > > Then if somehow I could have it report the position of the file the > > > EOF occurs I could then somehow count back to the first part of > > > the page then ummm well you see my confusion. Any help and > > suggestions > > > are appreciated. All though a solution would definitely solve > > > my problem > > > it wouldn't be fun at all :) > > > > The trick is to find whatever delimits the last page. It > > might be as simple as an ASCII formfeed (12) character. > > > > In general, you would seek to EOF, then back up a > > "reasonable" page size (say 2kb) and read a block of data. If > > you find the start of the last page, you're good. If not, > > back up another 2k and try again. > > > > > > > > However if I could get some hints or be pointed at some > > > relevant info I > > > would greatly appreciate it. Thanks in advance. > > > > There's a File::ReadBackwards module on CPAN that might be > > helpful. It handles all the file pointer manipulation for > > you. You could just read lines backwards into an array until > > you find the first line of the page. Then print > > reverse(@myarray) to print the last page. > > > > If the files were small, you could suck the whole file into a > > single string and extract the last page using a regex. But > > for big reports that's a bad idea... > > > > -- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
