I'd like to get the original command line used to run a script. The goal is to pipe some output to a second instance of the script, similar to using open(P,"|-"), except that the new invocation will be at the end of a sequence of piped commands. I'd like to do something like: open( P, "| prog1 | prog2 | -" ) so that the original name and arguments of the script is preserved (it could be symlinked, and it's required that the script itself needs to know the name) but this generates a runtime whine of sh: - not found.

I've come up with a couple of really hacked ideas to implement this, but the easiest would involve getting the full command line by which the script was invoked, so I could run: 

$originalcmdline = some magic code here ...;
open( P, "| prog1 | prog2 | $originalcmdline" );

[download]
and pump data into P.

Anticipating at least one answer, doing something like $originalcmdline = "$0 " . join(' ',@ARGV); won't work - strings in @ARGV could contain whitespace, quotes, double quotes, backslashes, wildcard characters, etc, making safe reconstruction of the command line a real pain.

Any suggestions?

In reply to Getting a script's original command line by blackwolf

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.