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Top Forums Shell Programming and Scripting Best practice for bracket comparisons? Post 302386513 by tlarkin on Tuesday 12th of January 2010 03:26:16 PM
Old 01-12-2010
Thanks for your reply, but still got a few questions...

According to this document, which I have used to teach myself shell programming, [[ and [ have different abilities in bash.

Quote:
Using the [[ ... ]] test construct, rather than [ ... ] can prevent many logic errors in scripts. For example, the &&, ||, <, and > operators work within a [[ ]] test, despite giving an error within a [ ] construct.
source: Test Constructs

I have also read that = is used for an integer comparison and == is used for a string comparison, but it also says that "=" and "==" are synonyms in that same document. So the double ='s is probably unneeded I take it, but still allowed?

I have been programming in shell for a while now and am just trying to clean up my bad habits, if any to become a more efficient coder. I ended up not hard coding the variable in either, and put the command in the comparison. The script works as I wrote it, but I am getting an odd exit status error when running it in the terminal.

Thanks again for your time.

Tom
 

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