* 'sigseen' in Build.sh goes away
* Signal name existence is checked in this order:
have our own¹ -> sys_signame[] -> _sys_signame[] -> build our own²
* Signal description existence is checked in this order:
sys_siglist[] -> _sys_siglist[] -> strsignal() -> NULL³
¹ Predefined list of items, for operating systems where we
cannot build² them, i.e. Plan 9 and Minix 3 (e.g. no $CPP -dD)
² The usual cpp(1) stuff
³ Changed later, see below
* Make $CPP test dependent on $NEED_MKSH_SIGNAME (others can
be added here, this is not absolute)
* Make signal name list generation² dependent on $NEED_MKSH_SIGNAME
* Fix check if the generation worked
* Guarantee that sigtraps[*].name and sigtraps[*].mess are valid
C strings; this makes the code shorter *and* removes a few pos-
sible nil pointer dereferences
* Embed autoconf'd usages of sys_sig* / strsignal / mksh_sigpairs
into inittraps()
* Check for each signal 0<=i<=NSIG that
name is not NULL or "" -> replace with ("%d", i)
mess is not NULL or "" -> replace with ("Signal %d", i)
name does not start (case-insensitive) with "SIG" -> name += 3
* In gettrap(), fix check if signal name starts, case-sensitive
or case-insensitive, depending on need, with "SIG" (bug from millert@)
Other changes:
* Build.sh: ac_test[n]() are documented
* Build.sh: ac_test[n]() can have negative prereqs as well now
* Build.sh: use <<-'EOF' consistently
* bump patchlevel to today
2f15a11c55