rust-chg: extract signal handlers from chg/procutil.c
abortmsgerrno() and debugmsg() are removed, and the public interface instead
returns success/error status. Since signal handlers can't propagate errors,
the result of kill() is just ignored.
#!/usr/bin/env python
from __future__ import absolute_import, print_function
import errno
import os
import sys
for f in sys.argv[1:]:
try:
print(f, '->', os.readlink(f))
except OSError as err:
if err.errno != errno.EINVAL:
raise
print(f, '->', f, 'not a symlink')
sys.exit(0)