39  Unix Scripting

39.1 Unix Scripting

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39.2 Unix Scripting slides

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39.3 Questions

39.3.1 Question 1

Which of the following are true about Unix variables?

Use $ both to set and access the value of a variable Use $ to access but not to set the value of a variable Only put $ in front of a variable when initializing a for loop Using $ in front of a variable is always optional

39.3.2 Question 2

What will this do?

for file in `ls *.txt`
do
  rm $file
  echo file deleted
done

Just list all of the files in your working directory Delete all .txt files in your working directory The same thing it would do if you used for file in $(ls *.txt) Print out a helpful message saying the names of the deleted files

39.3.3 Question 3

Which of the following are true of find -exec and find | xargs?

They both can be used to flexibly search for files and run commands on them. By default they can only run relatively simple commands. By using a child shell, they can run more complicated commands