Re: ia64 git pull

From: David A. Wheeler <dwheeler@dwheeler.com>
Date: Apr 22, 2005, 03:30 UTC
Message-ID: <42686FCA.2010605@dwheeler.com>
In-Reply-To: <17000.23588.462823.574142@sodium.jf.intel.com>

Petr Baudis <pasky@ucw.cz> writes:

>>Still, why would you escape it? My shell will not take # as a
>>comment start if it is immediately after an alphanumeric character.

I guess there MIGHT be some command shell implementation that stupidly _DID_ accept "#" as a comment character, even immediately after an alphanumeric. If that's true, then using # there would be a pain for portability.

But I think that's highly improbable. A quick peek at the Single Unix Specification as posted by the Open Group seems to say that, according to the standards, that's NOT okay: http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02 Basically, the command shell is supposed to tokenize, and "#" only means comment if it's at the beginning of a token.

And as far as I can tell, it's not an issue in practice either. I did a few quick tests on Fedora Core 3 and OpenBSD. On Fedora Core 3, I can say that bash, ash & csh all do NOT consider "#" as a comment start if an alpha precedes it. The same is true for OpenBSD /bin/sh, /bin/csh, and /bin/rksh. If such different shells do the same thing (this stuff isn't even legal C-shell text!), it's likely others do too.

--- David A. Wheeler