unix;)linux.

bruse · 10-24-2005, 09:33 AM

I have some trival doubt in unix and Linux.

In unix:
======

1)unix is open source or not?( i mean open or closed sou2)rce?)
It was invented in 1960's in AT&A(at that time FSF exist or not,If not where from the basic tools
has taken?like ls make pwd...
3)Does unix has kernal or not ?
4)If Yes Where can i get unix kernal source code?
5)All the unix flavare's are open sorce or not?

In Linux:
=======

1)Can i release the Linux without changing the service script.
2)Just rename the distro name to my desired name And without out modify the intsallation script?

MensaWater · 10-24-2005, 10:35 AM

1) Have a look at this thread. It will give you details about the history of Unix and Linux.

http://www.linuxquestions.org/questi...5&pagenumber=1

In breif:
Linux IS open source - it was written from the ground up to LOOK like Unix but is NOT Unix.

Unix has two main streams:
System V = The AT&T developed Unix that started it all.
Berkley = The Free Unix that AT&T gave to universities that was largely enhanced by the University of California at Berkley (hence the name).

More detail:
System V is NOT open source. Most commercial variants of Unix (Solaris, HP-UX, AIX, True64, SCO) include some System V stuff. (Though Solaris recently released an open source version for x86.)

Berkley was the basis for open source Unix called *BSD such as FreeBSD and OpenBSD.

A lot of what was developed in Berkley found its way into the commercial versions (in fact up until a few years ago some of them were just value added versions of Berkley but then as noted above many of them started incorporating System V in as well.)

2) Didn't quite get that one - I think it may be answered by above though.

3) Unix and Linux both have kernels. The name changes depending on the variant/distro you are on.

4) You can't except for the BSD and x86 Solaris. Just do a Google search for BSD then for Solaris and you find how to get the distributions.

5) No MOST Unix flavors are NOT open source as noted above - only the BSD variants are.

Linux:
1) & 2) Refer to the GPL (Gnu License) to determine this - its more a lega question than a technical one. Essentially Open Source requires that you continue to make it open source and that you include notifications of where it came from within what you do.

foo_bar_foo · 10-24-2005, 03:19 PM

Richard Stallman, the founder of the GNU project and FSF that creates Linux tools worked at MIT.
disliked the fact that big commercial firms took his work to make proprietary versions
started GNU
Gnu is Not Unix
however from a software point of view GNU is of course unix.
the distinction is a legal one and a very questionable legal one at that.

Linux kernel is also a permutation of Unix kernel because it implements a major amount of POSIX standards.

Flames about to begin but truth is truth

edit: often people start with the "no code in common" thing and while i do not believe it is valid to say that is the only issue i compare at randome ancient unix sysV ls.c and modern GNU ls.c from coreutils-5.2.1. The two programs don't of course compare at all nor should they . One is ancient history and the other is modern but i find some suprising similarities in variable names for instance from unix sysV. (i looked for like 5 seconds)

Code:

DIR *dirf;
struct dirent *dentry;

from GNU coreutils

Code:

register DIR *dirp;
register struct dirent *next;

it's lke DNA, it's evidence of kinship

jlliagre · 10-25-2005, 01:22 AM

Quote:

More detail:
System V is NOT open source. Most commercial variants of Unix (Solaris, HP-UX, AIX, True64, SCO) include some System V stuff. (Though Solaris recently released an open source version for x86.)

Actually, Solaris is based on System V R4, its version 10 is indeed released under an open source license, but this is not limited to x86, the same source tree build both the SPARC and the x86/x64 binaries.

bruse · 10-25-2005, 01:32 AM

And one more basic doubt:

)

Is all the unix flavor's are purely depending on the FSF and GNU appilication?
Latest Linux kernal is incorporated with FSF and GNu appilication..But what abt command's and application of free and openBSD flavor's?

danimalz · 10-25-2005, 02:18 AM

why is this important to you....?

jlliagre · 10-25-2005, 03:06 AM

All the unix flavors are certainly not depending on Gnu software, but many of them are including, optionally or not, a lot of gnu stuff.

MensaWater · 10-25-2005, 07:23 AM

Quote:

Actually, Solaris is based on System V R4, its version 10 is indeed released under an open source license, but this is not limited to x86, the same source tree build both the SPARC and the x86/x64 binaries.

Actually you're not quite right. ORIGINALLY SunOS was Berkley derived and LATER added in SVR4. I did note in my original post that most commerical Unix has "System V" in it now. Solaris in fact retains Berkley stuff in it. Have a look at Solris' ucb/bin - 3 guesses what ucb stands for and the first 2 don't count. They have that because some of the original SunOS admins don't like the System V commands. Having worked on AT&T (and later NCR which AT&T bought and let run their computer side) SVR4 I was acutely aware of the differences in Solaris.

The deal with Unix/Linux is almost every good idea (and even some bad ones) that make it into one flavor will later make it into all the others. For example Sun came up with NFS & NIS and every variant has those avaialble now.

jtshaw · 10-25-2005, 12:17 PM

Quote:

Originally posted by foo_bar_foo

edit: often people start with the "no code in common" thing and while i do not believe it is valid to say that is the only issue i compare at randome ancient unix sysV ls.c and modern GNU ls.c from coreutils-5.2.1. The two programs don't of course compare at all nor should they . One is ancient history and the other is modern but i find some suprising similarities in variable names for instance from unix sysV. (i looked for like 5 seconds)

Code:

DIR *dirf; struct dirent *dentry;

from GNU coreutils

Code:

register DIR *dirp; register struct dirent *next;

it's lke DNA, it's evidence of kinship

I'm not sure I understand what your getting at here... Linux follows (or at least tries to follow) the POSIX standard which includes such things as the definition of the dirent struct. POSIX is an open standard defined in a way that people can actually implement the functionality in there system so that a program using the POSIX syscalls can easily compile and work from one POSIX OS to another.

The GNU code (like GNU's ls.c from coreutils) uses the standard POSIX syscalls and structs to do things. It is reasonable to expect something so simple as listing the files in a directory would have similarities if you looked at two implementations even if neither author saw the others work. In this case the variables name being the same isn't even that surprising as the name they both picked is the obvious and most descriptive name.

If you go to The Open Group's Specifications Issue and search for dirent you will see exactly what I mean.

jlliagre · 10-25-2005, 12:26 PM

Quote:

Actually you're not quite right.

Please explain what is not quite right in my sentence.

Quote:

ORIGINALLY SunOS was Berkley derived and LATER added in SVR4.

Sorry, but this is innacurate.

SunOS 4 was indeed based on Berkeley distribution, but SunOS 5 *is* based on AT&T System V Release 4 code.
It is true SVR4 include a BSD compatibility layer and includes some of BSD features, but SVR4 is not an extension of BSD, it is an extension of SVR3, I mean the kernel and all core utilisties are System V, not BSD.

The only true part of BSD that was kept with Solaris 2 and wasn't in SVR4 was the ufs filesystem, which is certainly BSD based.

MensaWater · 10-25-2005, 12:39 PM

4 came before 5 so my "orignally" seems correct.

jlliagre · 10-25-2005, 03:30 PM

You didn't answer my question, you quoted me:

Quote:

Actually, Solaris is based on System V R4, its version 10 is indeed released under an open source license, but this is not limited to x86, the same source tree build both the SPARC and the x86/x64 binaries.

telling something is not quite right there ...
Please tell me what it is.

lowpro2k3 · 10-25-2005, 07:26 PM

Quote:

Originally posted by foo_bar_foo

Code:

DIR *dirf; struct dirent *dentry;

from GNU coreutils

Code:

register DIR *dirp; register struct dirent *next;

it's lke DNA, it's evidence of kinship

I can't tell if this is a joke or not, but that is not similiar code...

'DIR' is a data type in C. The function opendir(3) returns a pointer to this type. See man 3 opendir.

'struct dirent' is another data type in C. A pointer to a struct dirent is returned for each directory entry (hence the name, dirent...). See man 3 readdir.

Trivial example of a basic ls program:

Code:

/* example */
#include <stdio.h>
#include <dirent.h>
#include <sys/types.h>

int main()
{
  DIR *dir;
  struct dirent *next;
  dir = opendir("/tmp");

  while(next = readdir(dir) != NULL)
    printf("%s\n", next->d_name);

  closedir(dir);
  return 0;
}

Again, I'll feel like an idiot if you were being sarcastic, but I'm just saying all of the coreutils are extremely easy to clone once you see their functionality. Tools like ls, cat, du, diff, find and others, an average C programmer does NOT need the source code to write clones of them.