Hi,

I'm trying to capture data from a linux device file; in the form: 

#!/../../perl -w

open(FF, "< /dev/mouse") || die "cannot open handle \n";
while (<FF>)  {
    $vr = $_;
    print $vr;

 }
close (FF);

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I keep getting the error "readline() on closed filehandle FF on line 3"

I've tried this with /dev/ttyS1 , /dev/usb/USB/scanner0 and /dev/fd0

This works fine if I use a test file, like : 

   open(FF, "< /path/to/file.txt" );

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Also, I tried this in the form: sysopen(FF, "/dev/fd0", O_RDONLY); but I always get the error that says "item O_RDONLY isn't numeric at line 3"

Why doen't the sysopen work ? why does the device file always seem closed or non-existent ?

I am using Linux 9 and Perl 5.8 . I would hope not to need any Perl modules for something this basic... Help Help..... Happi..

Edited by Chady -- code tags and minor formatting.

In reply to Linux device filehandle roadblock by happi

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