Beefy Boxes and Bandwidth Generously Provided by pair Networks
laziness, impatience, and hubris

Comment on

( #3333=superdoc: print w/replies, xml ) Need Help??
This little failing test case illustrates my question:
# Test error checking for piped system calls # We use 'boom', a non-existent command, for testing. use Test::More qw/no_plan/; use strict; ok_system_call("true"); ok_system_call("true|true"); not_ok_system_call("boom"); not_ok_system_call("boom|boom"); not_ok_system_call("true|boom"); not_ok_system_call("boom|true"); #################################3 sub ok_system_call { my $test = shift; my $expect_success = shift; $expect_success = 1 if not defined $expect_success; my $ok = (system($test) == 0); # my $exit_code = $? >> 8; # diag "exit code was: $exit_code"; return $expect_success ? ok($ok, $test) : ok(!$ok, $test); } sub not_ok_system_call { my $test= shift; return ok_system_call($test,0); }
The error checking doesn't work correctly on the last one ("boom|true"), so it fails. I believe this happens because although boom fails, something is sent through the pipe, and 'true' succeeds on the other end of the pipe. What's the best practicing for error checking a piped command so this case is covered?

In reply to best practices for checking system return values for piped commands? by markjugg

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 cooling their heels in the Monastery: (6)
    As of 2018-04-24 13:34 GMT
    Find Nodes?
      Voting Booth?