Re: FAQ 8.28 How can I call backticks without shell processing?

"s" == szr <szrRE@xxxxxxxxxxxxxxx> writes:

s> Uri Guttman wrote:
>>>>>>> "s" == szr <szrRE@xxxxxxxxxxxxxxx> writes:

>> perl -e '@e = qw( a b c ); open( $e, "-|", 'echo', @e ); print <$e>'
>> a b c
>>
>> echo printed its args with spaces as expected so it got 3 separate
>> args and not 'abc' as you claim it would.

s> Curious, I thought the behavior would be like:
s> $ perl -e '@e = qw( a b c ); print @e'
s> which yields 'abc', as I saw that after the first three arguement of the
s> normal 3 arg open() it appeared to take a list of additional args that
s> is passes to what ever you opened. I didn't know it separates them like
s> it does. Good to know.

you don't get what is happening there. perl is printing each element and
there is no separator so it appears you are concatenating. when you exec
with a list each argument is separated in the same way and it depends on
the exec'ed program how they will be used. echo puts spaces between them
which is why i chose that for the one liner. i could have used perl
again and it would not have put spaces in unless i made it do so (as
with "@e").

uri

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