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Re: bash null conditional



Craig White wrote:
I'm in my bash book and looking on web but can't seem to resolve this
simple problem.

$ if [ -n "grep A121 myfile.csv" ]; then echo "null"; fi
null

$ if [ -n "grep A125 myfile.csv" ]; then echo "null"; fi
null

A125 definitely is null when I just run the grep command in the quotes
but A121 definitely is not null.

What am I missing on the if/null operator here?

Craig

Have you tried
   $ if [ -n $(grep A121 myfile.csv) ]; then echo "null"; fi
   $ if [ -n $(grep A125 myfile.csv) ]; then echo "null"; fi

The double quotes make a string, but it looks like you which to be executing grep which is accomplished by using the $() notation. You could also use a pair of backticks surrounding the command.

Justin Willmert


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