You can only accept and deliver signals which your OS supports. To get a list of them, use e.g. 

perl -le "print for sort keys %SIG"

[download]

update: the OP was modified after my answer, which doesn't make any sense know. Originally the OP was asking about how to implement or use or deliver (I don't remember very well) the USR1 signal on Windows.

Output from the above snippet on my box (linux) 

ALRM
BUS
CHLD
CLD
CONT
FPE
HUP
... more signals...
UNUSED
URG
USR1
USR2
VTALRM
WINCH
XCPU
XFSZ

[download]

which is a list of the signals for that OS. I bet perl on windows features a different set of keys in %SIG.

In reply to Re: signals in win32? by shmem
in thread signals in win32? by gants

Title:
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, details, 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, summary, 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.