Re^2: Can I do this ???

in reply to Re: Can I do this ???
in thread Can I do this ???

This is already pretty nasty in Windoze batch programming where this "feature" is possible.

It is?

> type foo.cmd
perl -le "print q{FOOBAR=}, $ENV{FOOBAR}"
perl -e "$ENV{FOOBAR}=rand(9999)"
perl -le "print q{FOOBAR=}, $ENV{FOOBAR}"
[download]

This produces

FOOBAR=
FOOBAR=
[download]

Which seems to show that things are working as expected. Either that, or I suck at writing Windows batch files.

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Re^3: Can I do this ??? by MidLifeXis (Prior) on Jan 22, 2009 at 15:20 UTC
Windows batch processing. `@REM -------------------------------- @REM runme.cmd @echo off SET FOO=bar echo %FOO% echo Calling setter.cmd call setter.cmd echo After setter.cmd echo %FOO%` [download] `@REM --------------------------------- @REM setter.cmd echo "I am in setter." set FOO=biz echo Setters FOO = %FOO%` [download] `-------------------------------------- output -------------------------------------- bar Calling setter.cmd "I am in setter." Setters FOO = biz After setter.cmd biz` [download] The called sub command, setter.cmd, resets the environment of the caller. --MidLifeXis	[reply] [d/l] [select]
Re^4: Can I do this ??? by BrowserUk (Pope) on Jan 22, 2009 at 15:51 UTC
The reason that works is because there is no child process involved. The called script is processed by the calling process--in the same fashion as Perl's do `script.pl;`--and the changes are made to the current process' environment by the current process. The effect is exactly the same as: `## Called .pl $::ENV{ somekey } = 'somevalue'; ##calling script; do 'called.pl';` [download] Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice. "Too many [] have been sedated by an oppressive environment of political correctness and risk aversion."	[reply] [d/l] [select]
Re^5: Can I do this ??? by MidLifeXis (Prior) on Jan 22, 2009 at 16:02 UTC
Very true, and I should have made that point clear. What I meant to demonstrate is that a "typical" windows batch mode programming style (well, what I saw when I was in an environment where I had to care about those scripts) allows, even encourages, modifying the "parent" process from things that are called. --MidLifeXis	[reply]
Re^6: Can I do this ??? by BrowserUk (Pope) on Jan 22, 2009 at 16:09 UTC
Re^7: Can I do this ??? by rovf (Priest) on Jan 23, 2009 at 13:28 UTC


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Re^2: Can I do this ???

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