That said, that time for your cut seems almost to good to be true. You are sure that cut can't somehow detect that it is writing to the null device and simply skip it--like perl sort detects a null context and skips?

As it happens, in the very first run of cut I tried, I sent the output to a file; and yes, I was pleasantly surprised to see how fast this cut was. But, what utility could there be for the optimization you describe? If there is one, I sure can't think of it. And why should a no-op take 0.9s?

Anyway, FWIW: 

% time cut -d, -f"1-15" numbers.csv > out.csv
0.80s user 0.11s system 100% cpu 0.906 total
% wc out.csv
  500000   500000 29174488 out.csv
% head -1 out.csv
169,970,983,721,411,426,262,255,484,174,389,651,175,975,763
% tail -1 out.csv
936,347,232,520,436,359,208,737,788,226,731,497,755,746,812

[download]

the lowliest monk

In reply to Re^4: cut vs split (suggestions) by tlm
in thread cut vs split (suggestions) by sk

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.