[~]> perldoc -f sysread
You need to install the perl-doc package to use this program.
[~]> 
-----------
cpan[4]> i /perl-doc/
No objects found of any type for argument /perl-doc/
----------
cpan[5]> install Perldoc
Perldoc is up to date (0.20).

cpan[6]> 
-----------
root@vblap:~# grep doc  /usr/local/lib/perl/5.10.0/perllocal.pod
=head2 Sat Jan  2 09:41:23 2010: C<Module> L<Perldoc|Perldoc>
C<EXE_FILES: perl-doc>
root@vblap:~# 
----------
[~]> perl-doc -f sysread
'-f' is an invalid option

Usage: perl-doc [options] [input-file]

Options:

    -v --version   - Print version of perl-doc
    --kwid-to-html - Convert input file or STDIN from kwid to html
[~]>