in reply to Re^3: Reading output of external program without Shell
in thread Reading output of external program without Shell

this doesn't call a shell

The code you showed does, but if you give run an arrayref, it does not (at least on *NIX):

$ perl -wMstrict -MIPC::Run=run -e' run "pstree -A $$" ' perl---sh---pstree $ perl -wMstrict -MIPC::Run=run -e' run ["pstree","-A",$$] ' perl---pstree

Replies are listed 'Best First'.
Re^5: Reading output of external program without Shell
by karlgoethebier (Abbot) on Nov 16, 2017 at 11:34 UTC
    "The code you showed does..."

    Ah, right. Thanks for correcting me. A precious hint.

    BTW, from the friendly manual:

    # Launch a sub process directly, no shell. Can't do redirection # with this form, it's here to behave like system() with an # inverted result. $r = run "cat a b c";

    Perhaps i missed something.

    "Es ist immer komplizierter" (Ludwig Marcuse)

    Still my favorite quote and motto.

    Best regards, Karl

    «The Crux of the Biscuit is the Apostrophe»

    perl -MCrypt::CBC -E 'say Crypt::CBC->new(-key=>'kgb',-cipher=>"Blowfish")->decrypt_hex($ENV{KARL});'Help

      Hm, you're right, it does say that!

      # Call this system's shell, returns TRUE on 0 exit code # THIS IS THE OPPOSITE SENSE OF system()'s RETURN VALUE run "cat a b c" or die "cat returned $?"; # Launch a sub process directly, no shell. Can't do redirection # with this form, it's here to behave like system() with an # inverted result. $r = run "cat a b c";

      I don't see how run would know that it is being called as run() or die vs. $r = run(). Also, I can't get it to work...

      $ perl -wMstrict -MIPC::Run=run -e' my $r = run "pstree -A $$" ' perl---sh---pstree

      Later on the docs say:

      run(), start(), and harness() can all take a harness specification as input. A harness specification is either a single string to be passed to the systems' shell

      And, on the other hand, the IPC::Run docs don't explicitly say that run [...] doesn't use the shell, although in the code you can find exec { $_[0] } @_;. It's all a bit confusing unfortunately.

        "...a bit confusing..."

        Yes. I asked the author. Best regards, Karl

        «The Crux of the Biscuit is the Apostrophe»

        perl -MCrypt::CBC -E 'say Crypt::CBC->new(-key=>'kgb',-cipher=>"Blowfish")->decrypt_hex($ENV{KARL});'Help