Hi again, Sorry for the delayed answer.
Thank you for all your comments (Yes Joseph, I will try to enhance my basic abilities - sorry for the bad code:-) My thoughts on this project was to make a perl script which copy the content of a tape to disk, no matter if it is tar archives, binary files, EBCDIC and so on, much like the UNIX tcopy. But, I work on Linux and don't have the tcopy available. When you write multiple files to a tape it creates an physical "end of file marker" at the end of each file. When some applications write to tape they make an EOF between each file and then a double EOF at the end of the tape. So, the idea was to stream out the data in a unaltered form to disk, creating a new file each time perl finds a EOF marker. I tried to use the binmode function, fx: binmode STDOUT; open BIN, "< $ARGV[0]"; open OUT, "> perltest.bin"; binmode BIN, ":raw:"; print OUT <BIN>; close BIN; close OUT; That give the all the content on the tape into one file. In conjunction with this I used the "read" function, but here I have to give a block size - and since the block size varies it does not work well! Fx one of the file types have a 3200 bit EBCDIC header followed by 400 byte binary header and the rest of the file can have any byte size. This means that I would have to chose 1 as block size to get everything out with "read", and that is a time consuming task (please correct me if I am wrong). I also looked at the "eof" function and tried to test the filehandle on this but with no luck. If you have any clues or suggestions I would really appreciate it. Thanks again, Jakob -----Oprindelig meddelelse----- Fra: David le Blanc [mailto:[EMAIL PROTECTED] Sendt: 12. marts 2004 02:18 Til: R. Joseph Newton; [EMAIL PROTECTED] Cc: [EMAIL PROTECTED] Emne: RE: Read from tape device > -----Original Message----- > From: R. Joseph Newton [mailto:[EMAIL PROTECTED] > Sent: Wednesday, 10 March 2004 5:37 PM > To: [EMAIL PROTECTED] > Cc: [EMAIL PROTECTED] > Subject: Re: Read from tape device > > [EMAIL PROTECTED] wrote: > > > Hi All, > > > > I am trying to read some data from af unix tape device. The > have several files with "end of file markers". Can I read > from tape devices at all? > > > > I tried "open" on the device and this one reads all files > on the tape into the first file and then hangs. Is it my code > (I know the first loop is not very good:-) or does perl not > recognise or honer the EOF marks? > > > > Thanks, > > Jakob > > > > my $cnt = 0; > > while (1 == 1) { > > open IN, "<", "/dev/nst0" || die "cant open ...\n"; > > while (@out = <IN>) { > > Why are you using an array?. That puts the read operator in > list context, so that it reads all lines of the file into the > @out array on the first round through the loop. > Isn't this a perfect example of when you should be using RECORD based I/O? What is the tape block size? > > > > $cnt++; > > Please use vowels. They are neither poisonous nor explosive. > > > > > open OUT, ">", "$cnt.bin" || die "cant open out\n"; > > print OUT "@out\n"; > > close OUT; > > } > > } > > close IN; > [snip] -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] <http://learn.perl.org/> <http://learn.perl.org/first-response>
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