print "Opening the file\n";                    open(F,"<$pair1[1]");
print "changing the mode to bin\n";
binmode F;
#binmode $new_sock;
my $bufsize = 100;
my $buffer=0;
my $n = sysread(F,$buffer,$bufsize);
print "the value of n is $n\n";                close(F);
[download]

That's better.

A few comments:

• Always check the result of a file open or I/O operation.
• You don't need to know the size of your file to use sysread. You can say how much sysread should read, and that function will return the number of bytes read, or 0 when it's finished.
• If you really need to know the file size, use a -s check.

Here is an example.

#!/usr/bin/perl
use warnings;
use strict;

my $filename = "stable.tar.gz"; # it's the latest Perl source code

die "filename not found\n" unless -f $filename;

my $size = -s $filename;

my $total_read = 0;

open F, "< $filename"
        or die "can't open $filename\n";

my $bufsize = 2_000_000;
my $buffer;

while ( my $read = sysread(F , $buffer , $bufsize,  ) )
{
    printf "Read %8u bytes\n", $read;
    # do something with $buffer
    $total_read += $read;
}

print "initial size: $size\n";
print "total read:   $total_read\n";
__END__
output:
Read  2000000 bytes
Read  2000000 bytes
Read  2000000 bytes
Read  2000000 bytes
Read  2000000 bytes
Read  2000000 bytes
Read   254916 bytes
initial size: 12254916
total read:   12254916
[download]

HTH

thanks for that
so if i give the buffer size the same as the size of the file what would happen. would it write the whole thing to the scalar at once or what?

and hey how do i change the mode back to normal.
like one mode is binmode. what is the other mode? how do i undo binmode?

You should re-read the docs more closely:

Returns the number of bytes actually read, 0 at end of file, or undef if there was an error (in the latter case $! is also set).

"What should it profit a man, if he should win a flame war, yet lose his cool?"