Expose valid signal set (sigfillset()): add signal.valid_signals()

[pitrou]

BPO	33332
Nosy	@pitrou, @vstinner, @njsmith, @csabella
PRs	bpo-33332: Add signal.valid_signals() #6581

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

Show more details

GitHub fields:

assignee = None
closed_at = <Date 2018-05-04.11:01:34.363>
created_at = <Date 2018-04-22.11:03:27.620>
labels = ['type-feature', '3.8']
title = 'Expose valid signal set (sigfillset()): add signal.valid_signals()'
updated_at = <Date 2018-05-04.13:29:30.265>
user = 'https://github.com/pitrou'

bugs.python.org fields:

activity = <Date 2018-05-04.13:29:30.265>
actor = 'pitrou'
assignee = 'none'
closed = True
closed_date = <Date 2018-05-04.11:01:34.363>
closer = 'pitrou'
components = []
creation = <Date 2018-04-22.11:03:27.620>
creator = 'pitrou'
dependencies = []
files = []
hgrepos = []
issue_num = 33332
keywords = ['patch']
message_count = 7.0
messages = ['315606', '316165', '316166', '316171', '316172', '316173', '316174']
nosy_count = 4.0
nosy_names = ['pitrou', 'vstinner', 'njs', 'cheryl.sabella']
pr_nums = ['6581']
priority = 'normal'
resolution = 'fixed'
stage = 'resolved'
status = 'closed'
superseder = None
type = 'enhancement'
url = 'https://bugs.python.org/issue33332'
versions = ['Python 3.8']

[pitrou]

See bpo-33329: it would be nice to expose a signal module function to get the set of user-actionable signals. Hopefully sigfillset() does that.

[pitrou]

New changeset 9d3627e by Antoine Pitrou in branch 'master':
bpo-33332: Add signal.valid_signals() (GH-6581)
9d3627e

[vstinner]

FYI on Fedora 27, I get:

>>> signal.NSIG
65
>>> set(range(0, signal.NSIG)) - signal.valid_signals()
{0, 33, 32}
>>> len(signal.valid_signals())
62
>>> min(signal.valid_signals())
<Signals.SIGHUP: 1>
>>> max(signal.valid_signals())
<Signals.SIGRTMAX: 64>

So signals 0, 32 and 33 are invalid, the first valid signal is 1 and the last is 64.

[csabella]

On Ubuntu 14.04, I get the same results as Victor.

[pitrou]

This is expected, see bpo-33329.

[vstinner]

+ if (sigemptyset(&mask) || sigfillset(&mask)) {

I'm not sure that sigemptyset() is needed.

sigfillset() manual page:

   sigfillset() initializes set to full, including all signals.

The function is used to *initialize* a set.

[pitrou]

Yes, but we're not losing anything by being overly cautious.