Re: List of packages shipping shell scripts with bashisms + MBF proposal
Clint Adams <email@example.com> writes:
> On Sat, Feb 09, 2008 at 04:39:11PM -0800, Russ Allbery wrote:
>> This one is somewhat arguable. Pure POSIX doesn't allow signal numbers,
>> but the XSI extension to POSIX does and dash and posh both support them.
>> We do not, in general, accept XSI extensions, but it's hard to argue
>> strongly for excluding a feature that even posh supports.
> Since 0.5.6, it does not; the only number it understands is the
> pseudo-signal 0, mandated by POSIX.
> The reason POSIX doesn't allow numbers is that they are inconsistent
> from platform to platform. People who learn signals on a commercial OS
> of yore sometimes assume that signal 5 means something other than
> SIGTRAP on Debian, and script traps and kills that end up not doing what
> is intended.
The XSI option to SUSv3 does not say that numeric signal numbers
are interpreted in a system-specific way. It is very specific
that numeric 1 is SIGHUP, 2 is SIGINT, 3 is SIGQUIT, 6 is
SIGABRT, 9 is SIGKILL, 14 is SIGALRM, and 15 is SIGTERM: