[Toybox] [PATCH] tail: support -f on BSD too.

[Rob Landley]

On 5/23/19 6:30 PM, enh via Toybox wrote:
> Factor out the inotify code and add a kqueue equivalent.
> 
> Specifically tested on macOS 10.14, but I assume this works for other
> BSDs too, given that I worked from the FreeBSD man page...

I moved it to lib/portability.c to keep all the #ifdefs in one place. (Well, two
counting both portability.h and .c.) And I got rid of the globals because I try
to have all the globals be in "this" (per-commandb TT.blah) or "toys" (global
context ala toys.optargs), plus libbbuf, toybuf, and toy_list.

I don't 100% stick to that though:

nm --size-sort generated/unstripped/toybox  | grep -v ' [Ttr] ' | grep -v GLIBC
0000000000000001 b completed.6972
0000000000000008 b do_lines_bridge
0000000000000008 b grgidbuf.10485
0000000000000008 b pwuidbuf.10470
0000000000000008 b tempfile2zap
000000000000000c b gnum.10521
000000000000000c b unum.10516
0000000000000020 D confstrs
0000000000000020 d toy_paths.9901
0000000000000028 b chattr
0000000000000028 d cp_preserve
0000000000000030 D others
0000000000000038 D polnames
0000000000000050 B toys
00000000000000e0 D pathconfs
0000000000000150 d e2attrs
00000000000001a0 d signames
0000000000000230 d scan_key_list
00000000000002d0 d fstypes
0000000000000380 D limits
0000000000000570 d typos
00000000000007b0 D sysconfs
0000000000001000 B libbuf
0000000000001000 B toybuf
0000000000001960 D toy_list
0000000000002028 B this

I should figure out how to convert more of that to rodata (without having to
propagate "const" down through call chains: a char * points to a string constant
that will segfault if you write to it half the time but if you pass a const to a
non-const * the compiler FLIPS OUT)...

Anyway, yet another thing on my 1.0-ish todo list. (Eventual cleanup.)

Rob