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$* vs. $@ [BASH]


 
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# 1  
Old 07-23-2009
$* vs. $@ [BASH]

In this document, the author has given a brief explanation of the Bash positional parameters, as well as some special variables, $*, $@, $#, and so on. She then makes this statement:

Quote:
"The implementation of "$*" has always been a problem and realistically should have been replaced with the behavior of "$@". In almost every case where coders use "$*", they mean "$@". "$*" Can cause bugs and even security holes in your software."
I believe I understand the difference in behaviour between the two, but I am not grasping what the security implications are. Would anyone care to give me some understanding about this? Is the use of $* potentially dangerous? If so, why?
# 2  
Old 07-23-2009
Arguments that were meant to be treated as a unit (single entity) should be treated that way. It doesn't mean that things will be insecure, but a program may assume that it's getting single entity arguments and dividing things up could result in a violation (something that can be exploited).

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