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Message-ID: <1418898565.5106.19.camel@linuxfoundation.org>
From: Richard Purdie <richard.purdie@linuxfoundation.org>
To: Richard Tollerton <rich.tollerton@ni.com>
Date: Thu, 18 Dec 2014 10:29:25 +0000
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References: <1418865078-10484-1-git-send-email-rich.tollerton@ni.com>
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Cc: bitbake-devel@lists.openembedded.org
Subject: Re: [PATCH] data: Avoid attempting to assign readonly shell vars
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On Wed, 2014-12-17 at 19:11 -0600, Richard Tollerton wrote:
> Attempting to set a read-only shell variable kills the shell. This is
> required POSIX behavior, it can't be disabled, and it's implemented by
> both dash and bash (although it seems to have only started happening in
> bash 4.3 and later, and only when run as /bin/sh).
> 
> This breaks `bitbake -c devshell` if bash 4.3 is installed, because
> BASHOPTS (and a boatload of other shell variables) are readonly.
> 
> The fix is to attempt to modify the variable in a subshell before doing
> the assignment.

Isn't this going to involve fork() calls for every single shell
variable? There must be a better way to do this?

Cheers,

Richard