On 3/5/12 5:21 PM, fabrizio gennari wrote:
> Hello.
>
> I tried to build bash-4.2 for the DJGPP (GNU for MS-DOS)
> platform. It had been done before, but the latest available version was
> 2.04.
>
> Something interesting has been found in the process. First:
> version.c protects the use of snprintf with #if defined
> (HAVE_SNPRINTF). But HAVE_SNPRINTF is always defined, only it is
> defined as 0 if snprintf is not available. Here is a patch to fix that.
It's interesting that djgpp would somehow require this. snprintf *is*
always available; if libc doesn't provide it, bash uses the replacement
function in lib/sh/snprintf.c. There are other places in the code
(e.g., builtins/mapfile.c) where it uses snprintf unconditionally. I'd
be more interested in why the replacement function is apparently not
being used here.
> Second, the variable
> job_control is only declared when JOB_CONTROL is #define'd. Yet, there
> is one case where its use is not protected by a suitable #if. Here's a
> patch to fix that.
This is bash-4.2 patch 18.
> Third, a comment in posixdir.h says "Posix does not
> require that the d_ino field be present, and some systems do not
> provide it". But the #if statement immediately above seems to implay
> that all non-Posix systems have it, because it assumes that it is
> always present if _POSIX_SOURCE is not defined. The following patch
> conditions the use of d_ino to the fact that configure successfully
> tests it, independently of _POSIX_SOURCE. Also, it avoids using
> d_fileno not only when d_ino is broken, but also when it is missing
> altogether.
Thanks. This is good. It's always better to use feature checks instead
of relying on something like _POSIX_SOURCE.
>
> If the above patches were applied, it would be a big step
> towards having a new version of bash for DJGPP. It wouldn't be enough,
> because DJGPP does not support the signals SIGCHLD and SIGWINCH and the
> flag SA_RESTART. And the code would improve anyway, because they fixed
> some little-tested cases.
I'll take a look at where these are used without testing for their presence.
Chet
--
``The lyf so short, the craft so long to lerne.'' - Chaucer
``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, ITS, CWRU c...@case.edu http://cnswww.cns.cwru.edu/~chet/
