chore, check for strerrno() function in c.ac

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
minor, print errno \t strerrno \t strerror, and provide a stub strerrno() if it's not there

Signed-off-by: Sebastian Freundt <freundt@ga-group.nl>
Merge branch 'feat/strerrno' into next

* feat/strerrno:
  minor, print errno \t strerrno \t strerror, and provide a stub strerrno() if it's not there
  chore, check for strerrno() function in c.ac
Merge branch 'next'

* next:
  minor, print errno \t strerrno \t strerror, and provide a stub strerrno() if it's not there
  chore, check for strerrno() function in c.ac
  fix, PEBKAC, use subshell again for test/test-suite.log output