General Things

[shanmuganathan]

Hi all,
I am new to unix and needed some clarificatons.I would be very thankful to all who reply.
1.Difference between BSD and AT&T System v relese 4.
2.Difference between hard an soft links.
I would like to know whether any software is there to practise HP commands on a windows PC where there is no server.

Best Regards,
NS Nathan.

[Mark Grant · Accepted solution]

Difference between BSD and AT&T is not that great from the user/sysadmin point of view and shouldn't really trouble you. There are minor differnces such as default print spooler and startup script layout and a few bits and bobs.

Hard links are two names for the same file and soft links are one file that is essentially a pointer to another. They basically achieve the same thing except you can not hard link a file from one filesystem to another (because it is basically two inodes for the same file and each filesystem has its own inode table).

If you remove the file a hard link points to, the data stays on the disk and is referenced by the link name as if that was the real name of the file. If you remove the data that a soft link points to you end up with no data, just a link that points to nothing.

[Jim Mulshine]

There is software like UWIN which provide a Korn shell (ksh). With such software installed on your windows pc you could practice many unix commands (like ln for creating hard and soft links), but not all hpux commands.

[Sridhar Bhaskarla]

Hi,

Mark gave you plenty of information.

Try to load cygwin from cygwin.com site. It will emulate unix on windows. You can practice general unix commands. You will need to have the HP-UX system as the commands specific to HP like LVM etc., are available on HP systems only.

-Sri

[Vijaya Kumar_3]

I hope now-a-days, people started thinking differently. Now Sun, HP, IBM and Linux are the major unix vendors and they have split into two standards, BSD and System V R4.

Solaris is the one the System V implementation and have some BSD features too. The difference between System V and BSD can be easily learned once you are comfortable with one Unix flavor, say Solaris or HP-UX.

To practice unix in our home, there is great way to install Redhat Linux Or Fedora Linux Or even Suse linux in our home PC and practice Unix. Also There is an Intel Version of Solaris available from Sun.

-Vijay

[Kenneth Platz]

You know... you can *buy* an HP-UX workstation off eBay -- they're not that expensive. I went ahead and bought me a C180 last year for around $200. That way you could have a box at home to practice on with actual HP-UX commands.

[Jeff Schussele]

Hi NS Nathan,

Difference between hard and symbolic (soft) links would be:

1) Hard links are created with the same ownership & perms as the link destination & any change to the link changes the destination as well.
2) Symbolic links are created with ownership/perms of the creator & creator's umask. Changes to the link do nothing to the destination & in fact are ignored by the system.
3) Symbolic links can span filesystems - hard links cannot.

HTH,
Jeff

[Jean-Luc Oudart]

Difference between BSD and SYSTEM V.
historical development.
http://www.cgd.ucar.edu/gds/thibaud/UNIX-tips/Tips/sysv-bsd.html

Regards,
JL

[Anoop P_2]

And how do one differentiate between a soft link and a hard link, by looking at an ls-al output?

[Jeroen Peereboom]

A Soft link is shown with '->' to another file.
Hard links show up because of the link count column (value greater than 1).

Softlink is created with 'ln -s',
hard links with 'ln'.

JP