Commit Briefs
fix buf_alloca error handling
Left-over from how OpenRCS/OpenCVS do error handling. OK stsp@
add O_CLOEXEC (close-on-exec) flag to open(2) calls
suggested by millert ok thomas_adam
got_error_from_errno -> got_error_prefix_errno
also add got_error_prefix_errno2 and got_error_prefix_errno3 which should hopefully all be merged into a single function with variadic args (but can't alloc mem)