Re: Tail not accepting -c 123 anymore?

[Paul Eggert]

Mike Hearn <address@hidden> writes:

> That sounds like the one, yes. Though 5.3.0 doesn't seem to show it.

Odd; it shows it for me.

$ _POSIX2_VERSION=199209 tail -c 123
tail: cannot open `123' for reading: No such file or directory
$ tail --version | head -n 1
tail (GNU coreutils) 5.3.0

> I can't help but wonder why compatibility with standards from 1978

In coreutils' defense, the standard in question was the
latest-and-greatest version until 2001.  (And the 2001 standard broke
lots more shell scripts. :-)

> Unfortunately setting _POSIX2_VERSION doesn't help me. The errant
> command is inside the stub code of a generic installer builder which is
> widely distributed.

Well, to some extent the horse is out of the barn door already.  The
behavior you're objecting to is not just that of coreutils 5.3.0; it's
also that of Solaris 9 /bin/tail, for example, and I assume for many
other "tail" implementations.

If you're willing to assume just GNU/Linux, you can put
"_POSIX2_VERSION=200112" into a README file, or into a wrapper around
the nonportable installer.  If you want to be more portable than that,
you can edit the output of the buggy builder of nonportable
installers.  Or you can issue a warning if you detect a maintainer
using a buggy installer builder.  Perhaps there are other solutions (I
don't know the details of your situation).