Subject: Re: [PATCH] Convert open("-|") to qx{} calls

From: [email-masked] (Randal L. Schwartz)
Date: 23 Feb 2006 12:41:44 -0800

>>>>> "Johannes" == Johannes Schindelin <[email-masked]> writes:

Johannes> Now that our local Perl guru joined the discussion, may I ask what
Johannes> is, and what is not quoted when put inside qx{}?

Nothing is quoted.  Your string acts as if it was XXX in:

        sh -c 'XXX'

so any quoting is entirely on your own.  Thus, without the multi-arg exec in
my proposed replacement, you can get shell-ish interactions that can ruin your
day pretty bad.

Johannes>  I had the
Johannes> impression that all arguments are quoted, except that variables are
Johannes> resolved first. Was that wrong? IOW does

Johannes> 	qx{bash $variable}

Johannes> quote the value of $variable, or not?

The Perl $variable is expanded to its current contents.  But suppose the
contents are `date` (including the backquotes).  That would mean that a shell
would execute a date command, and *its* output would then contribute further
to the command invocation.

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