So, your "That's quite wrong", is quite wrong.

What part? You didn't contradict anything I said.

But if it makes you happy, the following is also true.

The problem is with Perl's handling of Windows return codes. Trying to force fit a 32-bit signed int into an unsigned char doesn't go :)

That's quite wrong.

The problem occurs when coercing the 32-bit unsigned value into 31 unsigned bits (a 32-bit signed value where negative has a special meaning). 

DWORD status;
...
GetExitCodeProcess(ProcessInformation.hProcess, &status);
ret = (int)status;

[download]

Forcing the value into 8 bits doesn't even happen when you see that warning. 

if (status < 0) {
    if (ckWARN(WARN_EXEC))
        Perl_warner(aTHX_ packWARN(WARN_EXEC), "Can't spawn \"%s\": %s
+", argv[0], strerror(errno));
        status = 255 * 256;
    }
    else
        status *= 256;            <---- coercion into 8 bits
    PL_statusvalue = status;
}

[download]

In reply to Re^6: Can't spawn "cmd.exe": by ikegami
in thread Can't spawn "cmd.exe": by emalossi

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.