Re^3: File::Binary:howto goto a position in file

Thnx, I've fixed it (without OO). If I try OO, like:

#! /usr/bin/perl

use strict  ;
use Fcntl 'SEEK_SET'; 
use IO::File ;

my $fh = new IO::File ;

$fh->open("fio.pl") ;

$fh->binmode() ;
$fh->setpos(4) ;

my $in ;
$fh->read($in,2) ;

printf "result: %s\n",unpack("A2",$in) ;


$fh->close() ;
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The output is: result: #! (thats no shift at all!)
But I get the idea that the biggest mistake has been made with the read command....
Also, what about perldoc IO::Handler:

$io->read ( BUF, LEN, [OFFSET] )
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I miss the explanation of the 3 variables BUF, LEN and OFFSET ?

Thanks
Luca

update: solved the seek issue: $fh->seek(5, SEEK_SET) ;
I guess the only thing I don't understand is the OFFSET. If I give that a number I get nothing... ?

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Re^4: File::Binary:howto goto a position in file by ikegami (Patriarch) on Mar 13, 2006 at 01:37 UTC
I don't know how good IO::File's docs are, but check these docs (to which I already linked): The values for WHENCE [which you called OFFSET] are 0 to set the new position in bytes to POSITION, 1 to set it to the current position plus POSITION, and 2 to set it to EOF plus POSITION (typically negative). For WHENCE you may use the constants SEEK_SET , SEEK_CUR , and SEEK_END (start of the file, current position, end of the file) from the Fcntl module. Returns 1 upon success, 0 otherwise. In other words, the second argument determines whether the first argument is relative to the front of the file, to the current position in the file, or to the end of the file.	[reply]
Re^5: File::Binary:howto goto a position in file by jeanluca (Deacon) on Mar 13, 2006 at 12:34 UTC
your link to the docs seems to be wrong!! Luca	[reply]
Re^6: File::Binary:howto goto a position in file by ikegami (Patriarch) on Mar 13, 2006 at 15:13 UTC
Fixed. You could have used the one in my earlier post.	[reply]