I’m currently working with alpine linux, trying to
port some existing systems over to this minimal OS. It’s not an easy task.
Currently my issue is with tcsh. It seems that tcsh
is triggering some kind of core dump every time it is called. Here’s the output
when it’s called:
(nil) current memory allocation:
free: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
used: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Total in use: 0, total free: 0
Allocated memory from 0x55bd1509d000 to 0xffffffffffffffff. Real top at 0x55bd1509d000
nbytes=64: Out of memory
I’ve been googling and going through alpine’s bug
tracker
but there’s no mention of tcsh in there system beside the day they committed
it to their repository. It is worth noting that the package is currently in
the testing branch
of their apk package manager so there were no guarantees. It is interesting
that there seems to be literally no evidence anyone else has run into this
issue. Also somewhat intriguing is the fact that the alpine maintainers have no
documented interest in moving tcsh to a stable branch anytime soon. I agree
that it’s probably an outdated tool, but still popular enough it should have
higher priority.
If anyone has any potential solutions shoot me an email.
UPDATE (February 12, 2018):
Having submitted the bug to the Alpine Linux issue tracker, I received a
pointer to a patch in the
openwrt
project that seems to fix this issue. At the very least, tcsh actually boots
and seems to function as a shell once it’s applied. I’m going to work on either
getting the patch committed to the actual alpine package repo or build a custom
tcsh for my system with the patch.
UPDATE 2 (February 27, 2018):
This patch has now been committed to alpine’s apk
repository. This took a
little more effort than expected, and there’s definitely still some open issues
with the package before it can be moved from the edge branch to the main
package repo branch. As referenced in the linked github PR, the musl libc
appears to break a lot of basic functionality in tcsh. As you can see
here the number and nature of regression tests failed
is somewhat alarming. However, by hand testing shows that basic functionality
needed for my project works. Who knows, maybe it will convince some old-timers
to switch to a more modern shell like bash ;).
It does however, bring up an interesting conversation about whether there is
sufficient motivation for these issues to ever be fixed. The last few remaining
active tcsh developers have no desire to work to get their package working
with an upstart libc like musl and musl developers have no motivation to
work on supporting a shell none of their target users actively rely on. I think
my work has fallen into a rather small demographic.
