[Dog Like Nature]

Now I can run all my old scripts from Solaris! Woo-hoo!

[P]

You most likely can in previous versions as well, by using zsh in ksh compability mode. Simply start it as ksh, ie make a symlink ksh -> zsh and start it that way.

[Dog Like Nature]

Originally posted by P:
You most likely can in previous versions as well, by using zsh in ksh compability mode. Simply start it as ksh, ie make a symlink ksh -> zsh and start it that way.

Thanks, I never knew that!

[[APi]TheMan]

Originally posted by P:
You most likely can in previous versions as well, by using zsh in ksh compability mode. Simply start it as ksh, ie make a symlink ksh -> zsh and start it that way.

Ah, much like sh, which is really a bit-for-bit copy of bash:

Code:
[theman@thefro: ~]$ ls -l `which sh`
-r-xr-xr-x  1 root  wheel  603488 10 Aug  2004 /bin/sh
[theman@thefro: ~]$ ls -l `which bash`
-rwxr-xr-x  1 root  wheel  603488 10 Aug  2004 /bin/bash

[P]

It is a copy - always thought it was a hardlink, that would have made more sense, but the inode numbers are different. The tricky part about ksh is that the ksh -> zsh link is not installed in versions pre-Tiger. I sort of suspect that all Apple did was install this link by default, or just make another copy.

[Angus_D]

Hard links are squiffy on HFS, though. Anyway, it's more accurate to say that sh is a copy of bash, since it's really just bash running in a compatibility mode.

[Moose]

Originally Posted by [APi]TheMan

Ah, much like sh, which is really a bit-for-bit copy of bash:

Code:
[theman@thefro: ~]$ ls -l `which sh`
-r-xr-xr-x  1 root  wheel  603488 10 Aug  2004 /bin/sh
[theman@thefro: ~]$ ls -l `which bash`
-rwxr-xr-x  1 root  wheel  603488 10 Aug  2004 /bin/bash

md5 works better at demonstrating that than ls.

[[APi]TheMan]

Originally Posted by Moose

md5 works better at demonstrating that than ls.

Ah, that it does:

Code:
[theman@thefro: ~]$ md5 `which sh`
MD5 (/bin/sh) = 324c44b00a33984ffe52a45d5c3213fb
[aorth@nacho: ~]$ md5 `which bash`
MD5 (/bin/bash) = 324c44b00a33984ffe52a45d5c3213fb

[Rainy Day]

Originally Posted by Moose

md5 works better at demonstrating that than ls.

And diff works even better!

Code:
> diff -s /bin/bash /bin/sh
Files /bin/bash and /bin/sh are identical

[Dog Like Nature]

...and cmp works even better:

Code:
cmp /bin/sh /bin/bash && echo "Identical"

[Rainy Day]

How is that better? When comparing binary files of this size, diff is faster than cmp, and has the advantage of better output options.

[Dog Like Nature]

Originally Posted by Rainy Day

How is that better? When comparing binary files of this size, diff is faster than cmp, and has the advantage of better output options.

In other UNIXes diff cannot handle binary files (it's line based), so typically old-schoolers will use cmp for binaries, and diff for text. Also course cmp exits at the first difference, whereas diff will continue to the end, showing all differences. That can make cmp much faster if we're not really interested in the differences themselves.

In this case, as we're just interested in whether or not the binaries are identical, cmp makes sense.

[Rainy Day]

Originally Posted by Dog Like Nature

In other UNIXes diff cannot handle binary files (it's line based)

GNU diff handles binaries quite efficiently. MacOS X and OpenBSD both use it (as do, i suspect, most modern BSD's).

Also course cmp exits at the first difference, whereas diff will continue to the end, showing all differences.

When comparing binary files, diff also stops at the first difference (and with the appropriate switches, will do so for text files too).

That can make cmp much faster if we're not really interested in the differences themselves.

As i said previously, diff outperforms cmp in binaries of this size (and perhaps of any size). It's very efficient.

In this case, as we're just interested in whether or not the binaries are identical, cmp makes sense.

Not really. diff is faster than cmp, has the advantage of better output options, and the command syntax for this operation is simpler. GNU diff ain't your Dad's diff anymore!

[P]

Not that it isn't entertaining or anything, but can either of you show any sort of evidence which method is faster? They're both part of the GNU diffutils, so it's likely that they share a certain amount of code and are very likely to be just as fast in many cases.

And I'm not just being obnoxious, I'd actually really like to know if there is any difference either way or the other.