Re: new tar behavior and --wildcards (proposed middle ground)
Both sides in this discussion seem to have valid concerns:
FOR making --wildcard the default
- compatibility with upstream
- compatibility with standards
- compatibility with other distributions
- whatever reasons POSIX had for this were probably sensible
- upstream's judgement on this is likely to be correct
AGAINST making --wildcard the default
- very difficult to figure out what scrips are affected
- mysterious breakage far into the future
- requires grubbing around and inserting --wildcard in many places
As a compromise that addresses some of the issues I would suggest the
following: go with upstream, but add some convenience code, to whit:
(1) Hot-wire tar to check an environment variable TAR_WILDCARD_DEFAULT
and activate the --wildcard option if set.
(2) Hot-wire tar to print a warning message to stderr if it
(a) is defaulting to the --no-wildcard behaviour and,
(b) it notices a filename that, had tar instead been
in --wildcards mode, would have been expanded.
If stderr is not hooked up, the warning could reasonably be sent
using syslog() instead. I wouldn't bother adding any mechanism
to shut these warnings off; if one really wants them shut off,
use either --wildcards or --no-wildcards.
Point (1) would allow people to easily check if some breakage is
caused by this change, or to use old scripts/sources without
contortions; and point (2) would serve to catch problems in scripts
that might otherwise elude us. Point (2) would be especially helpful
given that we're coming up on a release, so it would be nice to find
and correct all affected scripts as rapidly as possible.
--
Barak A. Pearlmutter
Hamilton Institute & Dept Comp Sci, NUI Maynooth, Co. Kildare, Ireland
http://www.bcl.hamilton.ie/~barak/
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