Bug 132973 - Timeout option not working when SIGALRM blocked
Timeout option not working when SIGALRM blocked
Product: Fedora
Classification: Fedora
Component: nc (Show other bugs)
All Linux
medium Severity medium
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Assigned To: Radek Vokal
Ben Levenson
Depends On:
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Reported: 2004-09-20 11:31 EDT by Florin Malita
Modified: 2007-11-30 17:10 EST (History)
0 users

See Also:
Fixed In Version:
Doc Type: Bug Fix
Doc Text:
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Clone Of:
Last Closed: 2004-09-21 04:41:09 EDT
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oVirt Team: ---
RHEL 7.3 requirements from Atomic Host:
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Attachments (Terms of Use)
Unblock SIGALRM (810 bytes, patch)
2004-09-20 11:34 EDT, Florin Malita
no flags Details | Diff

  None (edit)
Description Florin Malita 2004-09-20 11:31:21 EDT
From Bugzilla Helper:
User-Agent: Mozilla/5.0 (X11; U; Linux i686; rv:1.7.3) Gecko/20040914

Description of problem:
The timeout option (-w) relies on SIGALRM being delivered so if for
some reason that signal is blocked it will simply not work.

It bit me when using nc in a piranha/nanny external script: apparently
nanny blocks SIGALRM before executing the script so nc can hang for a
long time trying to connect despite the timeout option.

Version-Release number of selected component (if applicable):

How reproducible:

Steps to Reproduce:
1. launch nc with SIGALRM blocked, a short timeout (-w 2) and an
unreachable target

Actual Results:  nc hangs for a long time, until the connect() call
bails out.

Expected Results:  nc should have timed out after the specified interval.

Additional info:

This is pretty straightforward to fix: just unblock SIGALRM - see patch.
Comment 1 Florin Malita 2004-09-20 11:34:30 EDT
Created attachment 104018 [details]
Comment 2 Radek Vokal 2004-09-21 04:41:09 EDT
Fixed in nc-1.10-22

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