zfs discuss - Dec 2007 - /usr/bin and /usr/xpg4/bin differences

Hello,
        I am working on open solaris bugs .. and need to change the code of df
in the above two folders..

I would like to know why there are two df''s with diff options in the
respective folders..
/usr/bin/df is different is from /usr/xpg4/bin/df!!

Why is it so?? What is this xpg4 represent?


Thanks,
Sasidhar.
 
 
This message posted from opensolaris.org

Hi,

It''s a different version in terms of the Unix standard  it complies to:

http://docs.sun.com/app/docs/doc/816-5221/6mbcm38u8?l=en&a=view


On 12/16/07, KASTURI VENKATA SESHA SASIDHAR <sasidhar.kvs at gmail.com>
wrote:
> Hello,
>         I am working on open solaris bugs .. and need to change the code of
df in the above two folders..
>
> I would like to know why there are two df''s with diff options in
the respective folders..
> /usr/bin/df is different is from /usr/xpg4/bin/df!!
>
> Why is it so?? What is this xpg4 represent?
>
>
> Thanks,
> Sasidhar.
>
>
> This message posted from opensolaris.org
> _______________________________________________
> zfs-discuss mailing list
> zfs-discuss at opensolaris.org
> http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
>

-- 
_________________________________/ sengork.blogspot.com /????

On Dec 15, 2007 11:31 PM, KASTURI VENKATA SESHA SASIDHAR
<sasidhar.kvs at gmail.com> wrote:
> Hello,
>         I am working on open solaris bugs .. and need to change the code of
df in the above two folders..
>
> I would like to know why there are two df''s with diff options in
the respective folders..
> /usr/bin/df is different is from /usr/xpg4/bin/df!!
The code for both variants of df come from the same source
(usr/src/cmd/fs.d/df.c).  The xpg4 variant is compiled with -DXPG4.
After a build in usr/src/cmd/fs.d is complete you will see the
following:

$ ls df*
df          df.o        df.po.xpg4  df.xpg4
df.c        df.po       df.xcl      df.xpg4.o

It looks to me as though df becomes /usr/bin/df and df.xpg4 becomes
/usr/xpg4/bin/df.

-- 
Mike Gerdts
http://mgerdts.blogspot.com/

On Dec 16, 2007 1:16 AM, Sasidhar Kasturi <sasidhar.kvs at gmail.com>
wrote:
> Yes .. but have a look at the bug i am working on ..
> Bug id:6493125
>
> http://bugs.opensolaris.org/view_bug.do?bug_id=6493125
>
> Thank you,
>  Sasidhar.
I''m not sure what question you are asking...

1) Why are there two variants of df?

If this is the question, it is likely because Solaris already had df
that had some behavior that people had grown to depend on.  A
standards committee came along and said "We need the -P and -v option
and the formatting of these headers needs to be ... and these columns
needs to be like ...".  Sun needed to not disrupt existing customers
and needed XPG4 compliance to satisfy a potentially different set of
customers.  Thus, the XPG4 variant got some small changes that (at the
time?) weren''t appropriate for the traditional version.

There is some likelihood that the bug you are working on is not the
first time that the differences between the XPG4 variant and the
/usr/bin variant have decreased.

2) How could the same source code produce different output?

It looks as though enabling the -P option is pretty straightforward -
modification of the getopts() string at removal of the #ifdef at line
593 and getting rid of the #ifdef and corresponding #endif at lines
605 and 607 should be sufficient.

    590 #ifdef XPG4
    591 	while ((arg = getopt(argc, argv, "F:o:abehkVtgnlPZ")) != EOF)
{
    592 #else
    593 	while ((arg = getopt(argc, argv, "F:o:abehkVtgnlvZ")) != EOF)
{
    594 #endif
    595 		if (arg == ''F'') {
    596 			if (F_option)
    597 				errmsg(ERR_FATAL + ERR_USAGE,
    598 				    "more than one FSType specified");
    599 			F_option = 1;
    600 			FSType = optarg;
    601 		} else if (arg == ''V'' && ! V_option) {
    602 			V_option = TRUE;
    603 		} else if (arg == ''v'' && ! v_option) {
    604 			v_option = TRUE;
    605 #ifdef XPG4
    606 		} else if (arg == ''P'' && ! P_option) {
    607 			SET_OPTION(P);
    608 #endif

Of course, updating the usage error, man page, etc. would be
appropriate too.  You can see a few other "#ifdef XPG4" blocks that
show the quite small differences between the two variants.

Also... since there is nothing zfs-specific here, opensolaris-code may
be a more appropriate forum.

-- 
Mike Gerdts
http://mgerdts.blogspot.com/

KASTURI VENKATA SESHA SASIDHAR wrote:
> Hello,
>         I am working on open solaris bugs .. and need to change the code of
df in the above two folders..
> 
> I would like to know why there are two df''s with diff options in
the respective folders..
> /usr/bin/df is different is from /usr/xpg4/bin/df!!
> 
> Why is it so?? What is this xpg4 represent?
"man XPG4"  ;)

Rob++
-- 
|Internet: windsor at warthog.com                             __o
|Life: Rob at Carrollton.Texas.USA.Earth                    _`\<,_
|                                                       (_)/ (_)
|"They couldn''t hit an elephant at this distance."
|  -- Major General John Sedgwick