Hi all!
I use ion3 and now notion for about 4 years, first in GNU/Linux and now
in NetBSD.
In NetBSD, I started to customize my statusbar with statusd scripts,
adapting some from contrib and making some of them myself. But, I had
to make some ugly changes on them.
In order to make external commands work, I had to add os.execute("sleep
1") just after io.popen(). Yes, it worked and since I didn't have time
to investigate the problem, I worked that way a long time.
Now I decided to investigate the problem further. I made a small
statusd_test.lua script:
local test_timer = statusd.create_timer()
local function update_test()
local f = io.popen('echo x', 'r')
os.execute("sleep 1")
local value = f:read('*all')
statusd.inform("test", value)
test_timer:set(1000, update_test)
end
update_test()
Without os.execute("sleep 1"), I receive:
test: x
.
test: (null)
.
test: (null)
...
But, with os.execute("sleep 1"), it works fine.
I soon realized that time events were generated by SIGALRM. So there
could be anything related with signals. So, my investigations confirm
that a minor change is necessary to make it work. Just comment line 543
of libmainloop/signal.c:
sigaction(SIGCHLD, &sa, NULL);
And it works like a charm, but I don't know if it breaks other things.
I'm not a C programmer expert. So I'd like to ask you if you know why
it could be happening. If it works under GNU/Linux, it is probably
something regarding implementation of signals in NetBSD.
Do you have any idea?
Why SIGCHLD is being intercepted?
Thanks in advance.
--
Silas Silva
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