Beefy Boxes and Bandwidth Generously Provided by pair Networks
go ahead... be a heretic

Comment on

( #3333=superdoc: print w/replies, xml ) Need Help??

If you set up a SIGINT handler like mine, it will propagate the SIGINT to all children you track in %pids. That's all.

If you want SIGINT to also abort your main program, you must somehow abort the infinite loop in it. My examples stop as soon as all children have exited. That may or may not be sufficient. Perhaps you also need to set a "stop" flag inside the SIGINT handler, and modify the infinite loop to break as soon as the "stop" flag is set.

What your forked child processes do when they receive a SIGINT depends on what signal handler they have installed. They may simply ignore the signal. They may have the default handler installed that terminates the process. They may have a custom handler installed that does a completely different thing.

There is a convention for sending signals to abort a process gracefully, in order of decreasing politeness: First, you send SIGINT (i.e. tell the process "the user wants you to stop what you are doing") once or twice, and wait a little while. If that does not terminate the process, try SIGHUP (connection hang up) if the process runs on a terminal. (Daemons often abuse SIGHUP to re-read their configuration.) Next, try SIGTERM ("terminate now"). If even that does not work, and you don't care about data loss, nuke the process out of the process list by sending it the SIGKILL signal. That signal can not be caught, it WILL terminate the process without giving it a chance to save data.

Have a look at perlipc, especially the signals section, and at

Update: Also note that Windows has no concept of signals, just a few signals are emulated by the Perl ports for Windows, and the emulation is not perfect. I.e. don't use signals on Windows.


Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)

In reply to Re^5: SIG{INT} not handling CTRL-C ??? by afoken
in thread SIG{INT} not handling CTRL-C ??? by girishatreya2005

Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post; it's "PerlMonks-approved HTML":

  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.
  • Log In?

    What's my password?
    Create A New User
    and all is quiet...

    How do I use this? | Other CB clients
    Other Users?
    Others scrutinizing the Monastery: (10)
    As of 2018-06-25 20:25 GMT
    Find Nodes?
      Voting Booth?
      Should cpanminus be part of the standard Perl release?

      Results (128 votes). Check out past polls.